2008 Hummer H2 Owners Manual

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and your vehicle can stall. Stalling can also occur if you get your tailpipe under water. And, as long as your tailpipe is under water, you will never be able to start your engine. When you go through water, remember that when your brakes get wet, it may take you longer to stop. See Driving in Rain and on Wet Roads on page 4-33
for more information on driving through water.

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After Off-Road Driving Remove any brush or debris that has collected on the underbody, chassis, or under the hood. These accumulations can be a ﬁre hazard. After operation in mud or sand, have the brake linings cleaned and checked. These substances can cause glazing and uneven braking. Check the engine and oil coolers for mud accumulation. Thoroughly and carefully clean these devices to allow proper cooling. Check the body structure, steering, suspension, wheels, tires, and exhaust system for damage. Also, check the fuel lines and cooling system for any leakage. Your vehicle will require more frequent service due to off-road use. See the Maintenance Schedule for additional information. Assist Steps If your vehicle has removable side steps, remove the steps prior to off-roading to give your vehicle more ground clearance and to prevent damage to the vehicle from the side steps dragging and/or catching on obstacles. Notice: Do not drive off-road with the side steps attached to your vehicle. You can damage the side steps and/or your vehicle’s frame if they get caught or drag against an obstacle. This damage would not be covered by your vehicle’s warranty. Always remove the side steps prior to any off-road driving.

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Driving at Night Night driving is more dangerous than day driving because some drivers are likely to be impaired — by alcohol or drugs, with night vision problems, or by fatigue. Night riving tips include: (cid:129) Drive defensively. (cid:129) Do not drink and drive. (cid:129) Reduce headlamp glare by adjusting the inside

rearview mirror.

(cid:129) Slow down and keep more space between you and

other vehicles because your headlamps can only light up so much road ahead.

(cid:129) Watch for animals. (cid:129) When tired, pull off the road. (cid:129) Do not wear sunglasses. (cid:129) Avoid staring directly into approaching headlamps. (cid:129) Keep the windshield and all glass on your vehicle

clean — inside and out.

(cid:129) Keep your eyes moving, especially during turns

or curves.

No one can see as well at night as in the daytime. But, as we get older, these differences increase. A 50-year-old driver might need at least twice as much light to see the same thing at night as a 20-year-old.

Driving in Rain and on Wet Roads Rain and wet roads can reduce vehicle traction and affect your ability to stop and accelerate. Always drive slower in these types of driving conditions and avoid driving through large puddles and deep-standing or ﬂowing water.

{CAUTION:

Wet brakes can cause crashes. They might not work as well in a quick stop and could cause pulling to one side. You could lose control of the vehicle. After driving through a large puddle of water or a car/vehicle wash, lightly apply the brake pedal until the brakes work normally. Flowing or rushing water creates strong forces. Driving through ﬂowing water could cause your vehicle to be carried away. If this happens, you and other vehicle occupants could drown. Do not ignore police warnings and be very cautious about trying to drive through ﬂowing water.

Hydroplaning Hydroplaning is dangerous. Water can build up under your vehicle’s tires so they actually ride on the water. This can happen if the road is wet enough and you are going fast enough. When your vehicle is hydroplaning, it has little or no contact with the road. There is no hard and fast rule about hydroplaning. The best advice is to slow down when the road is wet. Other Rainy Weather Tips Besides slowing down, other wet weather driving tips include: (cid:129) Allow extra following distance. (cid:129) Pass with caution. (cid:129) Keep windshield wiping equipment in good shape. (cid:129) Keep the windshield washer ﬂuid reservoir ﬁlled. (cid:129) Have good tires with proper tread depth. See Tires

on page 5-55.

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Before Leaving on a Long Trip To prepare your vehicle for a long trip, consider having it serviced by your dealer/retailer before departing. Things to check on your own include: (cid:129) Windshield Washer Fluid: Reservoir full? Windows

clean — inside and outside?

(cid:129) Wiper Blades: In good shape?

Fuel, Engine Oil, Other Fluids: All levels checked? Lamps: Do they all work and are lenses clean? Tires: Are treads good? Are tires inﬂated to recommended pressure?

(cid:129) Weather and Maps: Safe to travel? Have

up-to-date maps?

Highway Hypnosis Always be alert and pay attention to your surroundings while driving. If you become tired or sleepy, ﬁnd a safe place to park your vehicle and rest. Other driving tips include: (cid:129) Keep the vehicle well ventilated. (cid:129) Keep interior temperature cool. (cid:129) Keep your eyes moving — scan the road ahead

and to the sides.

(cid:129) Check the rearview mirror and vehicle

instruments often.

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(cid:129) (cid:129) (cid:129) Hill and Mountain Roads Driving on steep hills or through mountains is different than driving on ﬂat or rolling terrain. Tips for driving in these conditions include: (cid:129) Keep your vehicle serviced and in good shape. (cid:129) Check all ﬂuid levels and brakes, tires, cooling

system, and transmission.

(cid:129) Going down steep or long hills, shift to a

lower gear.

{CAUTION:

If you do not shift down, the brakes could get so hot that they would not work well. You would then have poor braking or even none going down a hill. You could crash. Shift down to let the engine assist the brakes on a steep downhill slope.

{CAUTION:

Coasting downhill in NEUTRAL (N) or with the ignition off is dangerous. The brakes will have to do all the work of slowing down and they could get so hot that they would not work well. You would then have poor braking or even none going down a hill. You could crash. Always have the engine running and your vehicle in gear when you go downhill.

(cid:129) Stay in your own lane. Do not swing wide or cut

across the center of the road. Drive at speeds that let you stay in your own lane. Top of hills: Be alert — something could be in your lane (stalled car, accident).

(cid:129) Pay attention to special road signs (falling rocks

area, winding roads, long grades, passing or no-passing zones) and take appropriate action. See Off-Road Driving on page 4-13 for information about driving off-road.

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(cid:129) Winter Driving Here are some tips for winter driving: (cid:129) Have your vehicle in good shape for winter. (cid:129) You might want to put winter emergency supplies

in your vehicle.

Include an ice scraper, a small brush or broom, a supply of windshield washer ﬂuid, a rag, some winter outer clothing, a small shovel, a ﬂashlight, a red cloth, and a couple of reﬂective warning triangles. And, if you will be driving under severe conditions, include a small bag of sand, a piece of old carpet, or a couple of burlap bags to help provide traction. Be sure you properly secure these items in your vehicle. Also see Tires on page 5-55.

Driving on Snow or Ice Most of the time, those places where the tires meet the road probably have good traction. However, if there is snow or ice between the tires and the road, you can have a very slippery situation. You have a lot less traction, or grip, and need to be very careful.

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What is the worst time for this? Wet ice. Very cold snow or ice can be slick and hard to drive on. But wet ice can be even more trouble because it can offer the least traction of all. You can get wet ice when it is about freezing, 32°F (0°C), and freezing rain begins to fall. Try to avoid driving on wet ice until salt and sand crews can get there. Whatever the condition — smooth ice, packed, blowing, or loose snow — drive with caution.

If You Are Caught in a Blizzard If you are stopped by heavy snow, you could be in a serious situation. You should probably stay with your vehicle unless you know for sure that you are near help and you can hike through the snow. Here are some things to do to summon help and keep yourself and your passengers safe:

Turn on the hazard warning ﬂashers. Tie a red cloth to your vehicle to alert police that you have been stopped by the snow.

(cid:129) Put on extra clothing or wrap a blanket around you. If you do not have blankets or extra clothing, make body insulators from newspapers, burlap bags, rags, ﬂoor mats — anything you can wrap around yourself or tuck under your clothing to keep warm.

The Traction Control System (TCS) improves your ability to accelerate when driving on a slippery road. TCS improves your ability to accelerate. See If Your Vehicle is Stuck in Sand, Mud, Ice, or Snow on page 4-39. Even though you have TCS, slow down and adjust your driving to the road conditions. Under certain conditions, you might want to turn the TCS off, such as when driving through deep snow and loose gravel, to help maintain vehicle motion at lower speeds. See Traction Control System (TCS) on page 4-5 and StabiliTrak® System on page 4-7. The Antilock Brake System (ABS) improves your vehicle’s stability when you make a hard stop on a slippery road. Even though you have ABS, begin stopping sooner than you would on dry pavement. See Antilock Brake System (ABS) on page 4-4. (cid:129) Allow greater following distance on any slippery road. (cid:129) Watch for slippery spots. The road might be ﬁne

until you hit a spot that is covered with ice. On an otherwise clear road, ice patches can appear in shaded areas where the sun cannot reach, such as around clumps of trees, behind buildings, or under bridges. Sometimes the surface of a curve or an overpass can remain icy when the surrounding roads are clear. If you see a patch of ice ahead of you, brake before you are on it. Try not to brake while you are actually on the ice, and avoid sudden steering maneuvers.

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(cid:129) (cid:129) {CAUTION:

Snow can trap exhaust gases under your vehicle. This can cause deadly CO (carbon monoxide) gas to get inside. CO could overcome you and kill you. You cannot see it or smell it, so you might not know it is in your vehicle. Clear away snow from around the base of your vehicle, especially any that is blocking the exhaust pipe. And check around again from time to time to be sure snow does not collect there. Open a window just a little on the side of the vehicle that is away from the wind. This will help keep CO out.

Run your engine only as long as you must. This saves fuel. When you run the engine, make it go a little faster than just idle. That is, push the accelerator slightly. This uses less fuel for the heat that you get and it keeps the battery charged. You will need a well-charged battery to restart the vehicle, and possibly for signaling later on with the headlamps. Let the heater run for a while.

You can run the engine to keep warm, but be careful.

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Then, shut the engine off and close the window almost all the way to preserve the heat. Start the engine again and repeat this only when you feel really uncomfortable from the cold. But do it as little as possible. Preserve the fuel as long as you can. To help keep warm, you can get out of the vehicle and do some fairly vigorous exercises every half hour or so until help comes.

If Your Vehicle is Stuck in Sand, Mud, Ice, or Snow Slowly and cautiously spin the wheels to free your vehicle when stuck in sand, mud, ice, or snow. See Rocking Your Vehicle to Get It Out on page 4-40. If your vehicle has a traction system, it can often help to free a stuck vehicle. Refer to your vehicle’s traction system in the Index. If the stuck condition is too severe for the traction system to free the vehicle, turn the traction system off and use the rocking method.

{CAUTION:

If you let your vehicle’s tires spin at high speed, they can explode, and you or others could be injured. The vehicle can overheat, causing an engine compartment ﬁre or other damage. Spin the wheels as little as possible and avoid going above 35 mph (55 km/h) as shown on the speedometer.

For information about using tire chains on your vehicle, see Tire Chains on page 5-75.

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Rocking Your Vehicle to Get It Out First, turn the steering wheel left and right to clear the area around the front wheels. The traction control system activates when the system senses that the wheels are spinning. See Traction Control System (TCS) on page 4-5. Then, shift back and forth between REVERSE (R) and a forward gear, spinning the wheels as little as possible. To prevent transmission wear, wait until the wheels stop spinning before shifting gears. Release the accelerator pedal while you shift, and press lightly on the accelerator pedal when the transmission is in gear. By slowly spinning the wheels in the forward and reverse directions, you will cause a rocking motion that could free your vehicle. If that does not get your vehicle out after a few tries, it might need to be towed out. Or, you can use the recovery loops. If your vehicle does need to be towed out, see Towing Your Vehicle on page 4-51.

Recovery Loops

{CAUTION:

These loops, when used, are under a lot of force. Keep people away from the vicinity of the loops and any chains or cables during use. Always pull the vehicle straight out. Never pull on the loops at a sideways angle. The loops could break off and you or others could be injured from the chain or cable snapping back.

Notice: Never use the recovery loops to tow the vehicle. Your vehicle could be damaged and it would not be covered by warranty.

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Front of Vehicle

Your vehicle may have recovery loops at the front and rear of the vehicle. You may need to use them if you are stuck off-road and need to be pulled to some place where you can continue driving.

Rear of Vehicle

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First Aid Kit and Tool Kit The ﬁrst aid and tool kit is located in the storage bin behind the spare tire on SUV models. It is held in place with a hook and loop fastener strap. On SUT models, the kit is in the rear cargo compartment on the passenger side of the vehicle.

The kit includes a ﬁrst aid kit, a ﬂashlight, a tire pressure gage, and a multi-purpose tool set.

The tire pressure gage has a reset button in the gage stem. After taking a pressure reading, press the button to reset the gage to zero.

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Front Mounted Receiver

Your vehicle is equipped with a front mounted receiver. You can use the receiver with a power winch platform (described later in this section) or with other accessories. Never use the front mounted receiver to tow a trailer. You can use the front mounted receiver to tow your vehicle behind another. See Recreational Vehicle Towing on page 4-51.

Power Winch Platform You can use the power winch platform (if equipped) with an aftermarket winch. Connect the winch to the platform and wiring to the vehicle following the winch manufacturer’s guidelines. Notice: Do not use the winch platform to winch at a tension of more than 9,000 lbs. (4 082 kg). This would damage your vehicle’s frame. This damage would not be covered by your vehicle’s warranty. If you are using a winch to pull out another vehicle, follow the winch manufacturer’s guidelines and observe the following to prevent damage to your vehicle:

If possible, have your vehicle anchored from the opposite side of the winch to a solid, immovable object. If winching from the front, use both of the rear recovery loops. If winching from the rear, use both of the front recovery loops.

(cid:129) Put your transmission in NEUTRAL (N). (cid:129) Use your regular brakes to hold your vehicle in place and block the wheels to keep the vehicle from moving.

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(cid:129) Notice: Using a power winch with the transmission in gear to pull out another vehicle may damage the transmission. When operating a power winch, always leave the transmission in NEUTRAL (N). Notice: Driving your vehicle through an automatic car wash with the winch installed, can cause damage to your vehicle and the car wash. Always remove the winch from your vehicle before using an automatic car wash. See Washing Your Vehicle on page 5-103 for more information. If you are using a winch to pull out your own vehicle, follow the winch manufacturer’s guidelines for self recovery and observe the following to prevent damage to your vehicle: (cid:129) Do not self recover your vehicle by wrapping the winch cable around an object (such as a pulley block or tree) and attaching it back to your vehicle’s recovery loops.

(cid:129) Always attach the winch cable directly to a solid anchor directly in front of your vehicle to achieve a straight line pull.

Loading Your Vehicle It is very important to know how much weight your vehicle can carry. This weight is called the vehicle capacity weight and includes the weight of all occupants, cargo, and all nonfactory-installed options. Two labels on your vehicle show how much weight it may properly carry, the Tire and Loading Information label and the Certiﬁcation/Tire label.

{CAUTION:

Do not load your vehicle any heavier than the Gross Vehicle Weight Rating (GVWR), or either the maximum front or rear Gross Axle Weight Rating (GAWR). If you do, parts on your vehicle can break, and it can change the way your vehicle handles. These could cause you to lose control and crash. Also, overloading can shorten the life of your vehicle.

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Tire and Loading Information Label

The Tire and Loading Information label also shows the size of the original equipment tires (C) and the recommended cold tire inﬂation pressures (D). For more information on tires and inﬂation see Tires on page 5-55 and Inﬂation - Tire Pressure on page 5-61. There is also important loading information on the vehicle Certiﬁcation/Tire label. It tells you the Gross Vehicle Weight Rating (GVWR) and the Gross Axle Weight Rating (GAWR) for the front and rear axle. See “Certiﬁcation/Tire Label” later in this section.

Label Example

A vehicle speciﬁc Tire and Loading Information label is attached to the center pillar (B-pillar). With the driver’s door open, you will ﬁnd the label attached below the door lock post (striker). The tire and loading information label shows the number of occupant seating positions (A), and the maximum vehicle capacity weight (B) in kilograms and pounds.

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Steps for Determining Correct Load Limit 1. Locate the statement “The combined weight

of occupants and cargo should never exceed XXX kg or XXX lbs” on your vehicle’s placard.

2. Determine the combined weight of the driver

and passengers that will be riding in your vehicle.

3. Subtract the combined weight of the driver and passengers from XXX kg or XXX lbs.

4. The resulting ﬁgure equals the available

amount of cargo and luggage load capacity. For example, if the “XXX” amount equals 1400 lbs and there will be ﬁve 150 lb passengers in your vehicle, the amount of available cargo and luggage load capacity is 650 lbs (1400 − 750 (5 x 150) = 650 lbs).

5. Determine the combined weight of luggage

and cargo being loaded on the vehicle. That weight may not safely exceed the available cargo and luggage load capacity calculated in Step 4.

6. If your vehicle will be towing a trailer, the load

from your trailer will be transferred to your vehicle. Consult this manual to determine how this reduces the available cargo and luggage load capacity of your vehicle.

See Towing a Trailer on page 4-55 for important information on towing a trailer, towing safety rules and trailering tips.

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Example 1

Example 2

Item

Description Vehicle Capacity Weight for Example 1 = Subtract Occupant Weight 150 lbs (68 kg) × 2 = Available Occupant and Cargo Weight =

Total

Item

1,000 lbs (453 kg)

300 lbs (136 kg)

700 lbs (317 kg)

Description Vehicle Capacity Weight for Example 2 = Subtract Occupant Weight 150 lbs (68 kg) × 5 = Available Cargo Weight =

Total

1,000 lbs (453 kg)

750 lbs (340 kg)

250 lbs (113 kg)

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Refer to your vehicle’s tire and loading information label for speciﬁc information about your vehicle’s capacity weight and seating positions. The combined weight of the driver, passengers and cargo should never exceed your vehicle’s capacity weight.

Certiﬁcation/Tire Label

A vehicle speciﬁc Certiﬁcation/Tire label is attached to the rear edge of the driver’s door.

Example 3

Item

Description Vehicle Capacity Weight for Example 3 = Subtract Occupant Weight 200 lbs (91 kg) × 5 = Available Cargo Weight =

Total

1,000 lbs (453 kg)

1,000 lbs (453 kg)

0 lbs (0 kg)

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The label shows the gross weight capacity of your vehicle. This is called the GVWR (Gross Vehicle Weight Rating). The GVWR includes the weight of the vehicle, all occupants, fuel, and cargo. The Certiﬁcation/Tire label also tells you the maximum weights for the front and rear axles, called Gross Axle Weight Rating (GAWR). To ﬁnd out the actual loads on your front and rear axles, you need to go to a weigh station and weigh your vehicle. Your dealer can help you with this. Be sure to spread out your load equally on both sides of the centerline. Never exceed the GVWR for your vehicle, or the GAWR for either the front or rear axle. And, if you do have a heavy load, you should spread it out.

{CAUTION:

Do not load your vehicle any heavier than the Gross Vehicle Weight Rating (GVWR), or either the maximum front or rear Gross Axle Weight Rating (GAWR). If you do, parts on your vehicle can break, and it can change the way your vehicle handles. These could cause you to lose control and crash. Also, overloading can shorten the life of your vehicle.

Your warranty does not cover parts or components that fail because of overloading. The label will help you decide how much cargo and installed equipment your truck can carry. Using heavier suspension components to get added durability might not change your weight ratings. Ask your dealer to help you load your vehicle the right way.

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If you put things inside your vehicle — like suitcases, tools, packages, or anything else — they go as fast as the vehicle goes. If you have to stop or turn quickly, or if there is a crash, they will keep going.

{CAUTION:

Things you put inside your vehicle can strike and injure people in a sudden stop or turn, or in a crash.

(cid:129) Put things in the cargo area of your

vehicle. Try to spread the weight evenly.

(cid:129) Never stack heavier things, like

suitcases, inside the vehicle so that some of them are above the tops of the seats.

(cid:129) Do not leave an unsecured child

restraint in your vehicle.

(cid:129) When you carry something inside the vehicle, secure it whenever you can.

(cid:129) Do not leave a seat folded down

unless you need to.

There is also important loading information for off-road driving in this manual. See “Loading Your Vehicle for Off-Road Driving” under Off-Road Driving on page 4-13. Add-On Equipment When you carry removable items, you may need to put a limit on how many people you can carry inside your vehicle. Be sure to weigh your vehicle before you buy and install the new equipment. Notice: Overloading your vehicle may cause damage. Repairs would not be covered by your warranty. Do not overload your vehicle. Remember not to exceed the Gross Axle Weight Rating (GAWR) of the front or rear axle. The Cargo Weight Rating (CWR) is the maximum weight of the load your vehicle can carry. It does not include the weight of the people inside. But you can ﬁgure about 150 lbs (68 kg) for each seat. The total cargo load must not be more than your vehicle’s CWR.

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Towing

Towing Your Vehicle Consult your dealer/retailer or a professional towing service if you need to have your disabled vehicle towed. See Roadside Assistance Program on page 7-6. If you want to tow your vehicle behind another vehicle for recreational purposes (such as behind a motorhome), see “Recreational Vehicle Towing” following.

Recreational Vehicle Towing Recreational vehicle towing means towing your vehicle behind another vehicle – such as behind a motorhome. The two most common types of recreational vehicle towing are known as “dinghy towing” (towing your vehicle with all four wheels on the ground) and “dolly towing” (towing your vehicle with two wheels on the ground and two wheels up on a device known as a “dolly”).

With the proper preparation and equipment, many vehicles can be towed in these ways. See “Dinghy Towing” and “Dolly Towing,” following. Here are some important things to consider before you do recreational vehicle towing: (cid:129) What’s the towing capacity of the towing vehicle? Be sure you read the tow vehicle manufacturer’s recommendations.

(cid:129) How far will you tow? Some vehicles have

restrictions on how far and how long they can tow.

(cid:129) Do you have the proper towing equipment? See your dealer or trailering professional for additional advice and equipment recommendations. Is your vehicle ready to be towed? Just as you would prepare your vehicle for a long trip, you’ll want to make sure your vehicle is prepared to be towed. See Before Leaving on a Long Trip on page 4-34.

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(cid:129) 6. Release the parking brake only after the vehicle

being towed is ﬁrmly attached to the towing vehicle. You can use your vehicle’s front mounted receiver with the proper accessories to tow it. See “Front Mounted Receiver” under If Your Vehicle is Stuck in Sand, Mud, Ice, or Snow on page 4-39.

7. Turn the ignition to ACCESSORY. 8. Disconnect the battery if you are going to tow for

long distances or long periods of time.

When towing your vehicle for extended periods of time, start your vehicle as often as possible to prevent battery drain. This should only be done when the tow vehicle is parked.

Dolly Towing Your vehicle cannot be dolly towed. If you must tow your vehicle behind another, use the dinghy towing procedure listed previously. Notice: Dolly towing your vehicle will damage drivetrain components. Do not dolly tow your vehicle.

Dinghy Towing Use the following procedure to tow your vehicle: 1. Shift the transmission to PARK (P). 2. Turn the engine off, but leave the ignition in

ACCESSORY.

3. Firmly set the parking brake. 4. Securely attach the vehicle being towed to the

tow vehicle.

{CAUTION:

Shifting a full-time four-wheel-drive vehicle’s transfer case into NEUTRAL can cause your vehicle to roll even if the transmission is in PARK (P). You or others could be injured. Make sure the parking brake is ﬁrmly set before you shift the transfer case to NEUTRAL.

5. Shift the transfer case to NEUTRAL (N). See Full-Time Four-Wheel Drive on page 2-36 for the proper procedure to select the NEUTRAL position for your vehicle.

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Selectable Extended Rear Ride Height If your vehicle has this feature it comes as part of the electronically controlled air suspension system. The selectable rear ride height allows you to raise the rear of the vehicle about 2 inches (5 cm) over the normal ride height. This can be helpful when driving off-road where you may need more ground clearance to clear an obstacle.

The button that controls this feature is located on the instrument panel to the right of the steering wheel.

To use this feature, ensure that the following conditions are met:

The engine must be running.

(cid:129) All doors must be fully closed. The suspension will

not raise or lower if a door is open. The vehicle speed must be less than 40 mph (64 km/h). The system will not activate otherwise.

Press the height control button to raise the rear of the vehicle. A light in the button will begin to ﬂash as the rear of the vehicle rises. Once the extended height has been reached (this may take up to a minute), the warning light will stop ﬂashing and will stay lit while the vehicle is at the extended height. To lower the vehicle to the normal ride height, press the button again. The light in the button will ﬂash as the suspension lowers. When the light in the button stops ﬂashing and goes out, the suspension has reached the normal ride height. This feature will lower the vehicle to the normal height if vehicle speed exceeds 40 mph (64 km/h). You may also want to use this feature when ascending, descending or cresting a steep hill as this can help prevent the rear bumper from dragging on the base of the hill or prevent the vehicle from grounding out (high centering) on the crest of the hill. Do not use this feature when towing a trailer.

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(cid:129) (cid:129) Electronically Controlled Air Suspension System The electronically controlled air suspension, if equipped, keeps the rear of your vehicle level under all load conditions. The system maintains the vehicle at the currently selected ride height. There are two ride heights: Normal Ride Height and Extended Ride Height. The Extended Ride Height feature is only available if the vehicle speed is below 40 mph (64 km/h). If the vehicle is at Extended Ride Height and the speed exceeds 40 mph (64 km/h), the system will automatically return the vehicle to Normal Ride Height. The activation and deactivation of the Extended Ride Height feature is controlled by a switch on the instrument panel. The system includes a compressor, two height sensors and two air springs supporting the vehicle. The system is activated when the engine is started and deactivated when the ignition is returned to OFF. The engine must be running for the rear of the vehicle to be raised and the doors must be closed to enable a transition between Normal Ride Height and Extended Ride Height. You may hear the compressor running whilst the system is active and you may also hear the release of air similar to a hissing sound. This is normal.

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Load leveling will not function normally with the inﬂater hose attached to the inﬂator outlet. Remove the hose from the outlet when it is not in use. See Accessory Inﬂator on page 5-75. Overload and Overheat Protection Overload protection is designed to protect the air suspension system and is an indication to the driver that the vehicle is overloaded. If the rear suspension remains at a low height, the rear axle load has exceeded GAWR (Gross Axle Weight Rating). When the overload protection mode is activated, the compressor operates for about 30 seconds to one minute without raising the vehicle depending on the amount of overload. This will continue each time the ignition is turned on until the rear axle load is reduced below GAWR. The system may reactivate without cycling the ignition if some of the excess load is removed. If the total rear GAWR (Gross Axle Weight Rating) is reached, the suspension may be slightly less than level. This is normal and does not mean there is a problem with the air suspension.

In some instances the compressor may stop working due to being overheated. This is normal. In the instance of an abnormal overheat condition though the compressor will stop working and the SERVICE SUSPENSION SYSTEM will be displayed on the DIC. See DIC Warnings and Messages on page 3-56 for more information.

Towing a Trailer

{CAUTION:

If you do not use the correct equipment and drive properly, you can lose control when you pull a trailer. For example, if the trailer is too heavy, the brakes may not work well — or even at all. You and your passengers could be seriously injured. Pull a trailer only if you have followed all the steps in this section. Ask your dealer for advice and information about towing a trailer with your vehicle.

Notice: Pulling a trailer improperly can damage your vehicle and result in costly repairs not covered by your warranty. To pull a trailer correctly, follow the advice in this part, and see your dealer for important information about towing a trailer with your vehicle. To identify the trailering capacity of your vehicle, you should read the information in “Weight of the Trailer” that appears later in this section. Trailering is different than just driving your vehicle by itself. Trailering means changes in handling, acceleration, braking, durability and fuel economy. Successful, safe trailering takes correct equipment, and it has to be used properly. That is the reason for this part. In it are many time-tested, important trailering tips and safety rules. Many of these are important for your safety and that of your passengers. So please read this section carefully before you pull a trailer.

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If You Do Decide To Pull A Trailer If you do, here are some important points:

There are many different laws, including speed limit restrictions, having to do with trailering. Make sure your rig will be legal, not only where you live but also where you’ll be driving. A good source for this information can be state or provincial police.

(cid:129) Consider using a sway control. See “Hitches” later

in this section.

(cid:129) Do not tow a trailer at all during the ﬁrst 500 miles (800 km) your new vehicle is driven. Your engine, axle or other parts could be damaged. Then, during the ﬁrst 500 miles (800 km) that you tow a trailer, do not drive over 50 mph (80 km/h) and do not make starts at full throttle. This helps your engine and other parts of your vehicle wear in at the heavier loads.

(cid:129) You can tow in DRIVE (D). You may want to shift the transmission to THIRD (3) or, if necessary, a lower gear selection if the transmission shifts too often (e.g., under heavy loads and/or hilly conditions). See “Tow/Haul Mode” following.

Three important considerations have to do with weight:

the weight of the trailer the weight of the trailer tongue and the weight on your vehicle’s tires

Tow/Haul Mode Tow/Haul mode is used when using your vehicle to pull a large or heavy load or trailer. Tow/haul is also useful while pulling a load in rolling terrain, in stop-and-go traffic, or when you need improved low-speed control, such as when parking. The purpose of the tow/haul mode is to do the following: (cid:129) Reduce the frequency and improve the predictability of transmission shifts when pulling a heavy trailer or a large or heavy load.

(cid:129) Provide the same solid shift feel when pulling a

heavy trailer or a large or heavy load as when the vehicle is unloaded. Improve control of vehicle speed while requiring less accelerator pedal activity when pulling a heavy trailer or a large or heavy load.

4-56

(cid:129) (cid:129) (cid:129) (cid:129) (cid:129) (cid:129) Tow/Haul mode is most effective when the vehicle and trailer combined weight is at least 75 percent of the vehicle’s Gross Combination Weight Rating (GCWR). See “Weight of the Trailer” later in this section.

Press the button on the instrument panel to the right of the steering wheel to enable the tow/haul mode.

A light on the instrument panel will illuminate to indicate that tow/haul mode has been selected.

Press the button again to turn off Tow/Haul mode. The indicator light on the instrument panel will turn off. The vehicle will automatically turn off Tow/Haul mode every time it is started. Driving with Tow/Haul mode activated without a heavy load or with no trailer will cause reduced fuel economy and unpleasant engine and transmission driving characteristics, but will not cause damage. Grade Braking Transmission Grade Braking works in Tow/Haul mode to automatically downshift the transmission when the driver is braking. The purpose is to aid in braking or maintaining vehicle speeds on down-grades by shifting to a lower gear to utilize engine braking.

4-57

Weight of the Trailer How heavy can a trailer safely be? It depends on how you plan to use your rig. For example, speed, altitude, road grades, outside temperature and how much your vehicle is used to pull a trailer are all important. It can also depend on any special equipment that you have on your vehicle, and the amount of tongue weight the vehicle can carry. See “Weight of the Trailer Tongue” later in this section for more information.

Maximum trailer weight is calculated assuming only the driver is in the tow vehicle and it has all the required trailering equipment. The weight of additional optional equipment, passengers and cargo in the tow vehicle must be subtracted from the maximum trailer weight. Use the following chart to determine how much your vehicle can weigh, based upon your vehicle model and options.

Engine

Axle Ratio

Maximum Trailer Weight

**GCWR

6.2L V8 (SUV) 6.2L V8 (SUT)*

3.73
3.73

8,200 lbs (3 720 kg) 8,200 lbs (3 720 kg)

15,000 lbs (6 804 kg) 15,000 lbs (6 804 kg)

*Sport utility truck (SUT) models are neither designed nor intended to tow 5th wheel or gooseneck trailers. **The Gross Combination Weight Rating (GCWR) in the total allowable weight of the completely loaded vehicle and trailer including any passengers, cargo, equipment and conversions. The GCWR for your vehicle should not be exceeded.

Ask your dealer/retailer for our trailering information or advice, or write us at our Customer Assistance Offices. See Customer Assistance Offices on page 7-5 for more information.

4-58

Weight of the Trailer Tongue The tongue load (A) of any trailer is an important weight to measure because it affects the total gross weight of your vehicle. The Gross Vehicle Weight (GVW) includes the curb weight of the vehicle, any cargo you may carry in it, and the people who will be riding in the vehicle. If you have a lot of options, equipment, passengers or cargo in your vehicle, it will reduce the tongue weight your vehicle can carry, which will also reduce the trailer weight your vehicle can tow. If you will tow a trailer, you must add the tongue load to the GVW because your vehicle will be carrying that weight, too. See Loading Your Vehicle on page 4-44 for more information about your vehicle’s maximum load capacity.

The trailer tongue weight (A) should be 10 percent to 15 percent of the total loaded trailer weight (B), up to a maximum of 600 lbs (272 kg) with a weight carrying hitch. The trailer tongue weight (A) should be 10 percent to 15 percent of the total loaded trailer weight (B), up to a maximum of 1,000 lbs (454 kg) with a weight distributing hitch. Do not exceed the maximum allowable tongue weight for your vehicle. Choose the shortest hitch extension that will position the hitch ball closest to the vehicle. This will help reduce the effect of trailer tongue weight on the rear axle.

4-59

Your spare tire carrier is behind the tailgate. If your hitch extension is too short, the spare tire may interfere with trailer coupling or trailer tongue jack operation on some types of trailers. After you have loaded your trailer, weigh the trailer and then the tongue, separately, to see if the weights are proper. If they are not, you may be able to get them right simply by moving some items around in the trailer. Trailering may also be limited by the vehicle’s ability to carry tongue weight. Tongue weight cannot cause the vehicle to exceed the GVWR (Gross Vehicle Weight Rating) or the RGAWR (Rear Gross Axle Weight Rating). The effect of additional weight may reduce your trailering capacity more than the total of the additional weight.

Consider the following example: A vehicle model base weight is 5,500 lbs (2 495 kg); 2,800 lbs (1 270 kg) at the front axle and 2,700 lbs (1 225 kg) at the rear axle. It has a GVWR of 7,200 lbs (3 266 kg), a RGAWR of 4,000 lbs (1 814 kg) and a GCWR (Gross Combination Weight Rating) of 14,000 lbs (6 350 kg). The trailer rating should be:

You can expect tongue weight to be at least 10 percent of trailer weight (850 lbs (386 kg)) and because the weight is applied well behind the rear axle, the effect on the rear axle will be greater than just the weight itself, as much as 1.5 times as much. The weight at the rear axle could be 850 lbs (386 kg) X 1.5 = 1,275 lbs (578 kg). Since the rear axle already weighs 2,700 lbs (1 225 kg), adding 1,275 lbs (578 kg) brings the total to 3,975 lbs (1 803 kg). This is very close to, but within the limit for RGAWR as well. The vehicle is set to trailer up to 8,500 lbs (3 856 kg).

4-60

But let’s say your speciﬁc vehicle is equipped with some of the latest options and you have a front seat passenger and two rear seat passengers with some luggage and gear in the vehicle as well. You may add 300 lbs (136 kg) to the front axle weight and 400 lbs (181 kg) to the rear axle weight. Your vehicle now weighs:

Weight is still below 7,200 lbs (3 266 kg) and you may think that you should subtract 700 additional pounds (318 kg) from your trailering capacity to stay within GCWR limits. Your maximum trailer would only be 7,800 lbs (3 538 kg). You may go further and think you must limit tongue weight to less than 1,000 lbs (454 kg) to avoid exceeding GVWR. But, you must still consider the effect on the rear axle. Because your rear axle now weighs 3,100 lbs (1 406 kg), you can only put 900 lbs (408 kg) on the rear axle without exceeding RGAWR.

The effect of tongue weight is about 1.5 times the actual weight. Dividing the 900 lbs (408 kg) by 1.5 leaves you with being able to handle only 600 lbs (272 kg) of tongue weight. Since tongue weight is usually at least 10 percent of total loaded trailer weight, you can expect that the largest trailer your vehicle can properly handle is 6,000 lbs (2 721 kg). It is important that you make sure your vehicle does not exceed any of its ratings — GCWR, GVWR, RGAWR, Maximum Trailer Rating or Tongue Weight. The only way to be sure you are not exceeding any of these ratings is to weigh your vehicle and trailer. Total Weight on Your Vehicle’s Tires Be sure your vehicle’s tires are inﬂated to the upper limit for cold tires. You will ﬁnd these numbers on the Certiﬁcation label at the rear edge of the driver’s door or see Loading Your Vehicle on page 4-44. Then be sure you don’t go over the GVW limit for your vehicle, or the GAWR, including the weight of the trailer tongue. If you use a weight distributing hitch, make sure you don’t go over the rear axle limit before you apply the weight distribution spring bars.

4-61

Hitches It is important to have the correct hitch equipment. Crosswinds, large trucks going by and rough roads are a few reasons why you’ll need the right hitch.

Weight-Distributing Hitches and Weight Carrying Hitches

(A) Body-to-Ground Distance (B) Front of Vehicle

When using a weight-distributing hitch, the hitch must be adjusted so that the distance (A) remains the same both before and after coupling the trailer to the tow vehicle.

4-62

If you will be pulling a trailer that, when loaded, will weigh more than 5,000 lbs (2 268 kg) be sure to use a properly mounted weight-distributing hitch and sway control of the proper size. This equipment is very important for proper vehicle loading and good handling when driving. You should always use a sway control if your trailer will weigh more than these limits. You can ask a hitch dealer/retailer about sway controls. Safety Chains You should always attach chains between your vehicle and your trailer. Cross the safety chains under the tongue of the trailer to help prevent the tongue from contacting the road if it becomes separated from the hitch. Always leave just enough slack so you can turn with your rig. Never allow safety chains to drag on the ground. Trailer Brakes If your trailer weighs more than 2,000 lbs (900 kg) loaded, then it needs its own brakes – and they must be adequate. Be sure to read and follow the instructions for the trailer brakes so you’ll be able to install, adjust and maintain them properly.

Driving with a Trailer Towing a trailer requires a certain amount of experience. Before setting out for the open road, you’ll want to get to know your rig. Acquaint yourself with the feel of handling and braking with the added weight of the trailer. And always keep in mind that the vehicle you are driving is now a good deal longer and not nearly as responsive as your vehicle is by itself. Before you start, check all trailer hitch parts and attachments, safety chains, electrical connector, lamps, tires and mirror adjustment. If the trailer has electric brakes, start your vehicle and trailer moving and then apply the trailer brake controller by hand to be sure the brakes are working. This lets you check your electrical connection at the same time. During your trip, check occasionally to be sure that the load is secure, and that the lamps and any trailer brakes are still working.

Following Distance Stay at least twice as far behind the vehicle ahead as you would when driving your vehicle without a trailer. This can help you avoid situations that require heavy braking and sudden turns.

Passing You will need more passing distance up ahead when you’re towing a trailer. Because you are a good deal longer, you will need to go much farther beyond the passed vehicle before you can return to your lane.

Backing Up Hold the bottom of the steering wheel with one hand. Then, to move the trailer to the left, just move that hand to the left. To move the trailer to the right, move your hand to the right. Always back up slowly and, if possible, have someone guide you.

4-63

Making Turns Notice: Making very sharp turns while trailering could cause the trailer to come in contact with the vehicle. Your vehicle could be damaged. Avoid making very sharp turns while trailering. When you are turning with a trailer, make wider turns than normal. Do this so your trailer will not strike soft shoulders, curbs, road signs, trees or other objects. Avoid jerky or sudden maneuvers. Signal well in advance.

Turn Signals When Towing a Trailer The arrows on your instrument panel will ﬂash whenever you signal a turn or lane change. Properly hooked up, the trailer lamps will also ﬂash, telling other drivers you’re about to turn, change lanes or stop. When towing a trailer, the arrows on your instrument panel will ﬂash for turns even if the bulbs on the trailer are burned out. Thus, you may think drivers behind you are seeing your signal when they are not. It is important to check occasionally to be sure the trailer bulbs are still working.

Driving On Grades Reduce speed and shift to a lower gear before you start down a long or steep downgrade. If you do not shift down, you might have to use your brakes so much that they would get hot and no longer work well. You can tow in DRIVE (D). You may want to shift the transmission to THIRD (3) or, if necessary, a lower gear selection if the transmission shifts too often (e.g., under heavy loads and/or hilly conditions). You may also want to activate the tow/haul mode if the transmission shifts too often. See “Tow/Haul Mode” earlier. When towing at high altitude on steep uphill grades, consider the following: Engine coolant will boil at a lower temperature than at normal altitudes. If you turn your engine off immediately after towing at high altitude on steep uphill grades, your vehicle may show signs similar to engine overheating. To avoid this, let the engine run while parked (preferably on level ground) with the automatic transmission in PARK (P) for a few minutes before turning the engine off. If you do get the overheat warning, see Engine Overheating on page 5-27.

4-64

Parking on Hills

{CAUTION:

You really should not park your vehicle, with a trailer attached, on a hill. If something goes wrong, your rig could start to move. People can be injured, and both your vehicle and the trailer can be damaged.

But if you ever have to park your rig on a hill, here is how to do it: 1. Apply your regular brakes, but do not shift into

PARK (P) yet.

2. Have someone place chocks under the trailer

wheels.

3. When the wheel chocks are in place, release the regular brakes until the chocks absorb the load.

4. Reapply the regular brakes. Then apply your

parking brake and shift into PARK (P).

5. Release the regular brakes.

When You Are Ready to Leave After Parking on a Hill 1. Apply your regular brakes and hold the pedal down

while you:

start your engine, shift into a gear, and release the parking brake.

2. Let up on the brake pedal. 3. Drive slowly until the trailer is clear of the chocks. 4. Stop and have someone pick up and store the

chocks.

Maintenance When Trailer Towing Your vehicle will need service more often when you’re pulling a trailer. See the Maintenance Schedule for more on this. Things that are especially important in trailer operation are automatic transmission ﬂuid (do not overﬁll), engine oil, axle lubricant, belts, cooling system and brake system. Each of these is covered in this manual, and the Index will help you ﬁnd them quickly. If you are trailering, it is a good idea to review these sections before you start your trip. Check periodically to see that all hitch nuts and bolts are tight.

4-65

(cid:129) (cid:129) (cid:129) Trailer Wiring Harness Heavy-Duty Trailer Wiring Harness Package

Your vehicle is equipped with the seven-wire trailer towing harness. This harness with a seven-pin universal trailer connector is attached to a bracket on the hitch platform.

The seven-wire harness contains the following trailer circuits: (cid:129) Yellow: Left Stop/Turn Signal (cid:129) Dark Green: Right Stop/Turn Signal (cid:129) Brown: Taillamps (cid:129) White: Ground

Light Green: Back-up Lamps

(cid:129) Red/Black: Battery Feed* (cid:129) Dark Blue: Trailer Brake* *There is a location in the Underhood Fuse Block for these circuits, but they are not connected. They should be connected, and proper fuses installed, by your dealer/retailer or a qualiﬁed service center. If you are charging a remote (non-vehicle) battery, press the Tow/Haul mode button located at the end of the shift lever. This will boost the vehicle system voltage and properly charge the battery.

4-66

(cid:129) Electric Brake Control Wiring Provisions These wiring provisions are included with your vehicle as part of the trailer wiring package. These provisions are for an electric brake controller. The instrument panel contains blunt cut wires near the data link connector for the trailer brake controller. The harness contains the following wires: (cid:129) Dark Blue: Brake Signal to Trailer Connector (cid:129) Red/Black: Battery

Light Blue/White: Brake Switch

(cid:129) White: Ground It should be installed by your dealer/retailer or a qualiﬁed service center.

Trailer Recommendations You must subtract your hitch loads from the Cargo Weight Rating (CWR). CWR is the maximum weight of the load your vehicle can carry. It doesn’t include the weight of the people inside, but you can ﬁgure about 150 lbs. (68 kg) for each seat. The total cargo load must not be more than your vehicles CWR. Weigh your vehicle with your trailer attached, so that you won’t go over the GVWR or GAWR. If you are using a weight-distributing hitch, weigh the vehicle without the spring bars in place. You’ll get the best performance if you spread out the weight of your load the right way, and if you choose the correct hitch and trailer brakes. For more information see Towing a Trailer on page 4-55.

4-67

(cid:129) ✍ NOTES

4-68

Section 5

Service and Appearance Care

Service ............................................................5-3
Accessories and Modiﬁcations ..........................5-3
California Proposition 65 Warning .....................5-3
California Perchlorate Materials Requirements .....5-4
Doing Your Own Service Work .........................5-4
Adding Equipment to the Outside of

Your Vehicle ..............................................5-4
Fuel ................................................................5-5
Gasoline Octane ............................................5-5
Gasoline Speciﬁcations ....................................5-5
California Fuel ...............................................5-5
Additives .......................................................5-6
Fuels in Foreign Countries ...............................5-6
Filling the Tank ..............................................5-7
Filling a Portable Fuel Container .......................5-9
Checking Things Under the Hood .....................5-9
Hood Release ..............................................5-10
Engine Compartment Overview .......................5-12
Engine Oil ...................................................5-13
Engine Oil Life System ..................................5-16
Engine Air Cleaner/Filter ................................5-18
Automatic Transmission Fluid .........................5-21
Engine Coolant .............................................5-24
Coolant Surge Tank Pressure Cap ..................5-26
Engine Overheating .......................................5-27

Overheated Engine Protection

Operating Mode .........................................5-28
Cooling System ............................................5-29
Engine Fan Noise .........................................5-33
Power Steering Fluid .....................................5-34
Windshield Washer Fluid ................................5-35
Brakes ........................................................5-36
Battery ........................................................5-39
Jump Starting ...............................................5-40
Rear Axle .......................................................5-45
Four-Wheel Drive ............................................5-46
Front Axle ......................................................5-47
Bulb Replacement ..........................................5-48
Halogen Bulbs ..............................................5-48
Headlamps ..................................................5-48
Front Turn Signal and Parking Lamps ..............5-49
Daytime Running Lamps (DRL) .......................5-50
Roof Marker Lamps ......................................5-50
Taillamps, Turn Signal, Stoplamps and

Back-up Lamps .........................................5-51
Replacement Bulbs .......................................5-53
Windshield Wiper Blade Replacement ..............5-54
Tires ..............................................................5-55
Tire Sidewall Labeling ...................................5-56
Tire Terminology and Deﬁnitions .....................5-58

5-1

Section 5

Service and Appearance Care

Inﬂation - Tire Pressure .................................5-61
Tire Pressure Monitor System .........................5-62
Tire Pressure Monitor Operation .....................5-64
Tire Inspection and Rotation ...........................5-67
When It Is Time for New Tires .......................5-69
Buying New Tires .........................................5-70
Different Size Tires and Wheels ......................5-72
Uniform Tire Quality Grading ..........................5-72
Wheel Alignment and Tire Balance ..................5-74
Wheel Replacement ......................................5-74
Tire Chains ..................................................5-75
Accessory Inﬂator .........................................5-76
If a Tire Goes Flat ........................................5-78
Changing a Flat Tire .....................................5-78
Removing the Spare Tire and Tools (SUT) .......5-80
Removing the Spare Tire and Tools (SUV) .......5-84
Removing the Flat Tire and Installing the

Spare Tire ................................................5-88
Storing a Flat or Spare Tire and Tools (SUT) ...5-94
Storing a Flat or Spare Tire and Tools (SUV) ...5-96
Spare Tire ...................................................5-99
Appearance Care ..........................................5-100
Interior Cleaning .........................................5-100
Fabric/Carpet ..............................................5-101
Leather ......................................................5-102
Instrument Panel, Vinyl, and Other Plastic

Surfaces .................................................5-102
Wood Panels ..............................................5-103

5-2

Speaker Covers ..........................................5-103
Care of Safety Belts ....................................5-103
Weatherstrips .............................................5-103
Washing Your Vehicle ..................................5-103
Cleaning Exterior Lamps/Lenses ....................5-104
Finish Care ................................................5-104
Windshield, Backglass, and Wiper Blades .......5-105
Aluminum Wheels .......................................5-106
Tires .........................................................5-106
Sheet Metal Damage ...................................5-106
Finish Damage ...........................................5-107
Underbody Maintenance ...............................5-107
Chemical Paint Spotting ...............................5-107
Vehicle Care/Appearance Materials ................5-108
Vehicle Identiﬁcation .....................................5-109
Vehicle Identiﬁcation Number (VIN) ................5-109
Service Parts Identiﬁcation Label ...................5-109
Electrical System ..........................................5-110
Add-On Electrical Equipment .........................5-110
Windshield Wiper Fuses ...............................5-110
Power Windows and Other Power Options ......5-110
Fuses and Circuit Breakers ..........................5-110
Instrument Panel Fuse Block ........................5-111
Center Instrument Panel Fuse Block ..............5-112
Underhood Fuse Block ................................5-113
Capacities and Speciﬁcations ........................5-117

Service For service and parts needs, visit your dealer/retailer. You will receive genuine GM parts and GM-trained and supported service people. Genuine GM parts have one of these marks:

Accessories and Modiﬁcations When non-dealer/non-retailer accessories are added to your vehicle they can affect your vehicle’s performance and safety, including such things as, airbags, braking, stability, ride and handling, emissions systems, aerodynamics, durability, and electronic systems like antilock brakes, traction control and stability control. Some of these accessories could even cause malfunction or damage not covered by warranty. GM Accessories are designed to complement and function with other systems on your vehicle. Your GM dealer/retailer can accessorize your vehicle using genuine GM Accessories. When you go to your GM dealer/retailer and ask for GM Accessories, you will know that GM-trained and supported service technicians will perform the work using genuine GM Accessories. Also, see Adding Equipment to Your Airbag-Equipped Vehicle on page 1-75.

California Proposition 65 Warning Most motor vehicles, including this one, contain and/or emit chemicals known to the State of California to cause cancer and birth defects or other reproductive harm. Engine exhaust, many parts and systems (including some inside the vehicle), many ﬂuids, and some component wear by-products contain and/or emit these chemicals.

5-3

If you want to do some of your own service work, you should use the proper service manual. It tells you much more about how to service your vehicle than this manual can. To order the proper service manual, see Service Publications Ordering Information on page 7-15. Your vehicle has an airbag system. Before attempting to do your own service work, see Servicing Your Airbag-Equipped Vehicle on page 1-75. You should keep a record with all parts receipts and list the mileage and the date of any service work you perform. See Maintenance Record on page 6-16.

Adding Equipment to the Outside of Your Vehicle Things you might add to the outside of your vehicle can affect the airﬂow around it. This can cause wind noise and can affect fuel economy and windshield washer performance. Check with your dealer/retailer before adding equipment to the outside of your vehicle.

California Perchlorate Materials Requirements Certain types of automotive applications, such as airbag initiators, seat belt pretensioners, and lithium batteries contained in remote keyless entry transmitters, may contain perchlorate materials. Special handling may be necessary. For additional information, see www.dtsc.ca.gov/hazardouswaste/perchlorate.

Doing Your Own Service Work

{CAUTION:

You can be injured and your vehicle could be damaged if you try to do service work on a vehicle without knowing enough about it.

(cid:129) Be sure you have sufficient knowledge,

experience, the proper replacement parts, and tools before you attempt any vehicle maintenance task.

(cid:129) Be sure to use the proper nuts, bolts, and

other fasteners. English and metric fasteners can be easily confused. If you use the wrong fasteners, parts can later break or fall off. You could be hurt.

5-4

Fuel Use of the recommended fuel is an important part of the proper maintenance of your vehicle. To help keep the engine clean and maintain optimum vehicle performance, we recommend the use of gasoline advertised as TOP TIER Detergent Gasoline.

Gasoline Octane Use premium unleaded gasoline with a posted octane rating of 91 or higher. You can also use regular unleaded gasoline rated at 87 octane or higher, but your vehicle’s acceleration could be slightly reduced, and you might notice a slight audible knocking noise, commonly referred to as spark knock. If the octane is less than 87, you might notice a heavy knocking noise when you drive. If this occurs, use a gasoline rated at 87 octane or higher as soon as possible. Otherwise, you could damage the engine. If you are using gasoline rated at 87 octane or higher and you hear heavy knocking, the engine needs service.

Gasoline Speciﬁcations At a minimum, gasoline should meet ASTM speciﬁcation D 4814 in the United States or CAN/CGSB-3.5 or 3.511 in Canada. Some gasolines contain an octane-enhancing additive called methylcyclopentadienyl manganese tricarbonyl (MMT). We recommend against the use of gasolines containing MMT. See Additives on page 5-6 for additional information.

California Fuel If your vehicle is certiﬁed to meet California Emissions Standards, it is designed to operate on fuels that meet California speciﬁcations. See the underhood emission control label. If this fuel is not available in states adopting California emissions standards, your vehicle will operate satisfactorily on fuels meeting federal speciﬁcations, but emission control system performance might be affected. The malfunction indicator lamp could turn on and your vehicle might fail a smog-check test. See Malfunction Indicator Lamp on page 3-42. If this occurs, return to your authorized dealer/retailer for diagnosis. If it is determined that the condition is caused by the type of fuel used, repairs might not be covered by your warranty.

5-5

Some gasolines that are not reformulated for low emissions can contain an octane-enhancing additive called methylcyclopentadienyl manganese tricarbonyl (MMT); ask the attendant where you buy gasoline whether the fuel contains MMT. We recommend against the use of such gasolines. Fuels containing MMT can reduce the life of spark plugs and the performance of the emission control system could be affected. The malfunction indicator lamp might turn on. If this occurs, return to your dealer/retailer for service.

Fuels in Foreign Countries If you plan on driving in another country outside the United States or Canada, the proper fuel might be hard to ﬁnd. Never use leaded gasoline or any other fuel not recommended in the previous text on fuel. Costly repairs caused by use of improper fuel would not be covered by your warranty. To check the fuel availability, ask an auto club, or contact a major oil company that does business in the country where you will be driving.

Additives To provide cleaner air, all gasolines in the United States are now required to contain additives that help prevent engine and fuel system deposits from forming, allowing the emission control system to work properly. In most cases, you should not have to add anything to the fuel. However, some gasolines contain only the minimum amount of additive required to meet U.S. Environmental Protection Agency regulations. To help keep fuel injectors and intake valves clean, or if your vehicle experiences problems due to dirty injectors or valves, look for gasoline that is advertised as TOP TIER Detergent Gasoline. Also, your dealer/retailer has additives that will help correct and prevent most deposit-related problems. Gasolines containing oxygenates, such as ethers and ethanol, and reformulated gasolines might be available in your area. We recommend that you use these gasolines, if they comply with the speciﬁcations described earlier. However, E85 (85% ethanol) and other fuels containing more than 10% ethanol must not be used in vehicles that were not designed for those fuels. Notice: Your vehicle was not designed for fuel that contains methanol. Do not use fuel containing methanol. It can corrode metal parts in the fuel system and also damage plastic and rubber parts. That damage would not be covered under your warranty.

5-6

Filling the Tank

{CAUTION:

Fuel vapor burns violently and a fuel ﬁre can cause bad injuries. To help avoid injuries to you and others, read and follow all the instructions on the pump island. Turn off your engine when you are refueling. Do not smoke if you are near fuel or refueling your vehicle. Do not use cellular phones. Keep sparks, ﬂames, and smoking materials away from fuel. Do not leave the fuel pump unattended when refueling your vehicle. This is against the law in some places. Do not re-enter the vehicle while pumping fuel. Keep children away from the fuel pump; never let children pump fuel.

The fuel cap is located on the driver’s side of the vehicle.

Open the door to access the fuel cap. To remove the fuel cap, turn it slowly counterclockwise. While refueling, let the fuel cap hang by the tether, if it has one.

5-7

The TIGHTEN GAS CAP message will be displayed on the Driver Information Center (DIC) if the fuel cap is not properly installed. See DIC Warnings and Messages on page 3-56 for more information.

{CAUTION:

If a ﬁre starts while you are refueling, do not remove the nozzle. Shut off the ﬂow of fuel by shutting off the pump or by notifying the station attendant. Leave the area immediately.

If you need a new fuel cap, be sure to get

Notice: the right type. Your dealer/retailer can get one for you. If you get the wrong type, it may not ﬁt properly. This may cause your malfunction indicator lamp to light and may damage your fuel tank and emissions system. See Malfunction Indicator Lamp on page 3-42.

{CAUTION:

Fuel can spray out on you if you open the fuel cap too quickly. If you spill fuel and then something ignites it, you could be badly burned. This spray can happen if your tank is nearly full, and is more likely in hot weather. Open the fuel cap slowly and wait for any hiss noise to stop. Then unscrew the cap all the way.

Be careful not to spill fuel. Do not top off or overﬁll the tank and wait a few seconds after you have ﬁnished pumping before removing the nozzle. Clean fuel from painted surfaces as soon as possible. See Washing Your Vehicle on page 5-103. When replacing the fuel cap, turn it clockwise until it clicks. Make sure the cap is fully installed. The diagnostic system can determine if the fuel cap has been left off or improperly installed. This would allow fuel to evaporate into the atmosphere. See Malfunction Indicator Lamp on page 3-42.

5-8

Filling a Portable Fuel Container

{CAUTION:

Never ﬁll a portable fuel container while it is in your vehicle. Static electricity discharge from the container can ignite the fuel vapor. You can be badly burned and your vehicle damaged if this occurs. To help avoid injury to you and others:

(cid:129) Dispense fuel only into approved

containers.

(cid:129) Do not ﬁll a container while it is inside a

vehicle, in a vehicle’s trunk, pickup bed, or on any surface other than the ground. (cid:129) Bring the ﬁll nozzle in contact with the

inside of the ﬁll opening before operating the nozzle. Contact should be maintained until the ﬁlling is complete.

(cid:129) Do not smoke while pumping fuel. (cid:129) Do not use a cellular phone while

pumping fuel.

Checking Things Under the Hood

{CAUTION:

Things that burn can get on hot engine parts and start a ﬁre. These include liquids like fuel, oil, coolant, brake ﬂuid, windshield washer and other ﬂuids, and plastic or rubber. You or others could be burned. Be careful not to drop or spill things that will burn onto a hot engine.

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Hood Release To open the hood, do the following:

2. Pull the handle with

this symbol on it. It is located inside the vehicle to the lower left of the steering column.

1. Release both hood side latches.

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3. Then go to the front of the vehicle and pull the

assist handles toward you to lift the hood.

4. Pull the hood open until it is supported by the

cables.

Before closing the hood, be sure all ﬁller caps are on properly. To close the hood, do the following: 1. Hold up the hood a few inches from the closed position and then let it go so that it has enough force to engage the hood latch.

2. Pull up on the assist handles to be sure that the

hood is latched.

3. Latch both hood side latches.

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Engine Compartment Overview When you open the hood on the 6.2L V8 engine here is what you will see:

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A. Coolant Surge Tank. See Cooling System on

page 5-29 and Coolant Surge Tank Pressure Cap on page 5-26.

B. Engine Air Cleaner/Filter and Air Filter Restriction

Indicator (If Equipped). See Engine Air Cleaner/Filter on page 5-18.

C. Windshield Washer Fluid Reservoir. See “Adding

Washer Fluid” under Windshield Washer Fluid on page 5-35.

D. Engine Oil Fill Cap. See “When to Add Engine Oil”

under Engine Oil on page 5-13.

E. Engine Oil Dipstick. See “Checking Engine Oil”

under Engine Oil on page 5-13.

F. Air Filter Restriction Indicator (If Equipped). See Engine Air Cleaner/Filter on page 5-18. G. Automatic Transmission Fluid Dipstick. See “Checking the Fluid Level” under Automatic Transmission Fluid on page 5-21.

H. Engine Cooling Fan. See Cooling System on

page 5-29.

I. Remote Negative (−) Terminal (GND). See Jump

Starting on page 5-40.

J. Power Steering Fluid Reservoir (Out of View).

See Power Steering Fluid on page 5-34.

K. Remote Positive (+) Terminal. See Jump Starting on

page 5-40.

L. Brake Fluid Reservoir. See “Brake Fluid” under

Brakes on page 5-36.

M. Underhood Fuse Block. See Underhood Fuse Block

on page 5-113.

N. Battery. See Battery on page 5-39.

Engine Oil Checking Engine Oil It is a good idea to check the engine oil every time you get fuel. In order to get an accurate reading, the oil must be warm and the vehicle must be on level ground. The engine oil dipstick handle is a yellow loop. See Engine Compartment Overview on page 5-12
for the location of the engine oil dipstick. 1. Turn off the engine and give the oil several minutes to drain back into the oil pan. If you do not do this, the oil dipstick might not show the actual level.

2. Pull out the dipstick and clean it with a paper towel or cloth, then push it back in all the way. Remove it again, keeping the tip down, and check the level.

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When to Add Engine Oil

See Engine Compartment Overview on page 5-12
for the location of the engine oil ﬁll cap.

If the oil is below the cross-hatched area at the tip of the dipstick, add at least one quart/liter of the recommended oil. This section explains what kind of oil to use. For engine oil crankcase capacity, see Capacities and Speciﬁcations on page 5-117. Notice: Do not add too much oil. If the engine has so much oil that the oil level gets above the cross-hatched area that shows the proper operating range, the engine could be damaged.

Be sure to add enough oil to put the level somewhere in the proper operating range. Push the dipstick all the way back in when you are through.

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What Kind of Engine Oil to Use

These numbers on an oil container show its viscosity, or thickness. Do not use other viscosity oils such as SAE 20W-50.

(cid:129) Oils meeting these

requirements should have the starburst symbol on the container. This symbol indicates that the oil has been certiﬁed by the American Petroleum Institute (API).

Look for this information on the oil container, and use only those oils that are identiﬁed as meeting GM Standard GM6094M and have the starburst symbol on the front of the oil container. Notice: Use only engine oil identiﬁed as meeting GM Standard GM6094M and showing the American Petroleum Institute Certiﬁed For Gasoline Engines starburst symbol. Failure to use the recommended oil can result in engine damage not covered by your warranty.

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Look for three things: (cid:129) GM6094M

Your vehicle’s engine requires oil meeting GM Standard GM6094M. Look for and use only an oil that meets GM Standard GM6094M.

(cid:129) SAE 5W-30

As shown in the viscosity chart, SAE 5W-30 is best for your vehicle.

When the system has calculated that oil life has been diminished, it will indicate that an oil change is necessary. A CHANGE ENGINE OIL SOON message will come on. See DIC Warnings and Messages on page 3-56. Change the oil as soon as possible within the next 600 miles (1 000 km). It is possible that, if you are driving under the best conditions, the oil life system might not indicate that an oil change is necessary for over a year. However, the engine oil and ﬁlter must be changed at least once a year and at this time the system must be reset. Your dealer/retailer has trained service people who will perform this work using genuine parts and reset the system. It is also important to check the oil regularly and keep it at the proper level. If the system is ever reset accidentally, you must change the oil at 3,000 miles (5 000 km) since your last oil change. Remember to reset the oil life system whenever the oil is changed.

If you are in an area of extreme cold, where the temperature falls below −20°F (−29°C), it is recommended that you use either an SAE 5W-30
synthetic oil or an SAE 0W-30 oil. Both provide easier cold starting and better protection for the engine at extremely low temperatures. Engine Oil Additives Do not add anything to the oil. The recommended oils with the starburst symbol that meet GM Standard GM6094M are all you need for good performance and engine protection.

Engine Oil Life System When to Change Engine Oil Your vehicle has a computer system that lets you know when to change the engine oil and ﬁlter. This is based on engine revolutions and engine temperature, and not on mileage. Based on driving conditions, the mileage at which an oil change will be indicated can vary considerably. For the oil life system to work properly, you must reset the system every time the oil is changed.

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How to Reset the Engine Oil Life System The Engine Oil Life System calculates when to change the engine oil and ﬁlter based on vehicle use. Whenever the oil is changed, reset the system so it can calculate when the next oil change is required. If a situation occurs where you change the oil prior to a CHANGE ENGINE OIL SOON message being turned on, reset the system. Always reset the engine oil life to 100% after every oil change. It will not reset itself. To reset the Engine Oil Life System: 1. Display the OIL LIFE REMAINING on the DIC. 2. Press and hold the SET/RESET button on the DIC for more than ﬁve seconds. The oil life will change to 100%.

If the CHANGE ENGINE OIL SOON message comes back on when you start your vehicle, the Engine Oil Life System has not reset. Repeat the procedure.

What to Do with Used Oil Used engine oil contains certain elements that can be unhealthy for your skin and could even cause cancer. Do not let used oil stay on your skin for very long. Clean your skin and nails with soap and water, or a good hand cleaner. Wash or properly dispose of clothing or rags containing used engine oil. See the manufacturer’s warnings about the use and disposal of oil products. Used oil can be a threat to the environment. If you change your own oil, be sure to drain all the oil from the ﬁlter before disposal. Never dispose of oil by putting it in the trash, pouring it on the ground, into sewers, or into streams or bodies of water. Instead, recycle it by taking it to a place that collects used oil. If you have a problem properly disposing of used oil, ask your dealer/retailer, a service station, or a local recycling center for help.

5-17

Engine Air Cleaner/Filter

See Engine Compartment Overview on page 5-12
for the location of the engine air cleaner/ﬁlter and the air ﬁlter restriction indicator, if equipped.

When to Inspect the Engine Air Cleaner/Filter If your vehicle is equipped with an air ﬁlter restriction indicator, it lets you know when the engine air cleaner/ ﬁlter needs to be replaced. On vehicles with a restriction indicator, you should inspect the air ﬁlter restriction indicator at every oil change and replace the engine air cleaner/ﬁlter when the indicator tells you to. On vehicles without an air ﬁlter restriction indicator, you should inspect the air cleaner/ﬁlter at every oil change and replace it at the ﬁrst oil change after 100,000 miles (160 000 km). See Scheduled Maintenance on page 6-4
for more information.

If you spray water into the engine air

Notice: cleaner/ﬁlter intake and water enters the engine air cleaner/ﬁlter housing, as shown in the illustration, you could damage your vehicle’s engine. The repairs would not be covered by your warranty. Do not spray water into the engine air cleaner/ﬁlter intake and/or housing.

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How to Inspect the Engine Air Cleaner/Filter Vehicles With an Air Filter Restriction Indicator Locate the air ﬁlter restriction indicator on the engine air duct. When the indicator turns black or is in the red/orange change zone, replace the ﬁlter and reset the indicator. See “Inspecting the Engine Air Cleaner/Filter and Resetting the Air Filter Restriction Indicator” later in this section for further instructions. Vehicles Without an Air Filter Restriction Indicator To inspect the air cleaner/ﬁlter, remove it from the vehicle and lightly shake the ﬁlter to release loose dust and dirt. If the engine air cleaner/ﬁlter remains caked with dirt, a new ﬁlter is required. See “Inspecting the Engine Air Cleaner/Filter and Resetting the Air Filter Restriction Indicator” later in this section for further instructions.

Inspecting the Engine Air Cleaner/Filter and Resetting the Air Filter Restriction Indicator

1. Loosen the screws on the engine air cleaner/ﬁlter

cover.

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7. Reset the air ﬁlter restriction indicator, if equipped,

by pressing the top button on the indicator. If your vehicle is not equipped with the air ﬁlter restriction indicator, refer to the Maintenance Schedule to determine when to replace the engine air cleaner/ﬁlter. See Additional Required Services on page 6-6.

{CAUTION:

Operating the engine with the air cleaner/ﬁlter off can cause you or others to be burned. The air cleaner not only cleans the air; it helps to stop ﬂames if the engine backﬁres. If it is not there and the engine backﬁres, you could be burned. Do not drive with it off, and be careful working on the engine with the air cleaner/ﬁlter off.

If the air cleaner/ﬁlter is off, a backﬁre

Notice: can cause a damaging engine ﬁre. And, dirt can easily get into your engine, which will damage it. Always have the air cleaner/ﬁlter in place when you are driving.

2. Lift the cover upward and set it aside. 3. Pull the air cleaner/ﬁlter up and out from the air

cleaner housing. Care should be taken to dislodge as little dirt as possible.

4. Clean the air cleaner/ﬁlter sealing surfaces and

the housing.

5. Inspect or replace the engine air cleaner/ﬁlter. 6. Reinstall the cover and tighten the screws.

5-20

Automatic Transmission Fluid When to Check and Change Automatic Transmission Fluid It is usually not necessary to check the transmission ﬂuid level. The only reason for ﬂuid loss is a transmission leak or overheating the transmission. If you suspect a small leak, then use the following checking procedures to check the ﬂuid level. However, if there is a large leak, then it may be necessary to have the vehicle towed to a dealer/retailer service department and have it repaired before driving the vehicle further. Notice: Use of the incorrect automatic transmission ﬂuid may damage your vehicle, and the damages may not be covered by your warranty. Always use the automatic transmission ﬂuid listed in Recommended Fluids and Lubricants on page 6-12. Change the ﬂuid and ﬁlter at the intervals listed in the Maintenance Schedule. See Scheduled Maintenance on page 6-4. Be sure to use the transmission ﬂuid listed in Recommended Fluids and Lubricants on page 6-12.

How to Check Automatic Transmission Fluid Notice: Too much or too little ﬂuid can damage your transmission. Too much can mean that some of the ﬂuid could come out and fall on hot engine parts or exhaust system parts, starting a ﬁre. Too little ﬂuid could cause the transmission to overheat. Be sure to get an accurate reading if you check your transmission ﬂuid. Before checking the ﬂuid level, prepare your vehicle as follows: 1. Start the engine and park your vehicle on a level

surface. Keep the engine running.

2. Apply the parking brake and place the shift lever

in PARK (P).

3. With your foot on the brake pedal, move the shift lever through each gear range, pausing for about three seconds in each range. Then, move the shift lever back to PARK (P).

4. Allow the engine to idle (500 – 800 rpm) for at least

one minute. Slowly release the brake pedal.

5. Keep the engine running and press the Trip/Fuel

button or trip odometer reset stem until TRANS TEMP (Transmission Temperature) displays on the Driver Information Center (DIC).

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6. Using the TRANS TEMP reading, determine and

perform the appropriate check procedure. If the TRANS TEMP reading is not within the required temperature ranges, allow the vehicle to cool, or operate the vehicle until the appropriate transmission ﬂuid temperature is reached.

Cold Check Procedure Use this procedure only as a reference to determine if the transmission has enough ﬂuid to be operated safely until a hot check procedure can be made. The hot check procedure is the most accurate method to check the ﬂuid level. Perform the hot check procedure at the ﬁrst opportunity. Use this cold check procedure to check ﬂuid level when the transmission temperature is between 80°F and 90°F (27°C and 32°C). 1. Locate the transmission dipstick at the rear of the engine compartment, on the passenger side of the vehicle.

The dipstick handle has this graphic. See Engine Compartment Overview on page 5-12 for more information.

2. Flip the handle up, and then pull out the dipstick

and wipe it with a clean rag or paper towel.

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3. Install the dipstick by pushing it back in all the way, wait three seconds, and then pull it back out again. 4. Check both sides of the dipstick, and read the lower

level. Repeat the check procedure to verify the reading.

5. If the ﬂuid level is below the COLD check band, add only enough ﬂuid as necessary to bring the level into the COLD band. It does not take much ﬂuid, generally less than one pint (0.5L). Do not overﬁll.

6. Perform a hot check at the ﬁrst opportunity after

the transmission reaches a normal operating temperature between 160°F to 200°F (71°C to 93°C). 7. If the ﬂuid level is in the acceptable range, push the

dipstick back in all the way, then ﬂip the handle down to lock the dipstick in place.

Hot Check Procedure Use this procedure to check the transmission ﬂuid level when the transmission ﬂuid temperature is between 160°F and 200°F (71°C and 93°C). The hot check is the most accurate method to check the ﬂuid level. The hot check should be performed at the ﬁrst opportunity in order to verify the cold check. The ﬂuid level rises as ﬂuid temperature increases, so it is important to ensure the transmission temperature is within range. 1. Locate the transmission dipstick at the rear of the

engine compartment, on the passenger side of the vehicle.

The dipstick handle has this graphic. See Engine Compartment Overview on page 5-12 for more information.

2. Flip the handle up, and then pull out the dipstick

and wipe it with a clean rag or paper towel.

3. Install the dipstick by pushing it back in all the way, wait three seconds, and then pull it back out again.

4. Check both sides of the dipstick, and read the lower

level. Repeat the check procedure to verify the reading.

5. Safe operating level is within the HOT cross hatch band on the dipstick. If the ﬂuid level is not within

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