2009 GMC Sierra Owners Manual

Vehicle Storage

{ CAUTION:

Batteries have acid that can burn you and gas that can explode. You can be badly hurt if you are not careful. See Jump Starting on page 5-46 for tips on working around a battery without getting hurt.

Infrequent Usage: If the vehicle is driven infrequently, remove the black, negative (−) cable from the battery. This helps keep the battery from running down. Extended Storage: For extended storage of the vehicle, remove the black, negative (−) cable from the battery or use a battery trickle charger. This helps maintain the charge of the battery over an extended period of time.

Jump Starting If the vehicle is a Two-mode Hybrid, see the Two-mode Hybrid manual for more information. If the vehicle’s battery (or batteries) has run down, you may want to use another vehicle and some jumper cables to start your vehicle. Be sure to use the following steps to do it safely.

{ CAUTION:

Batteries can hurt you. They can be dangerous because:

(cid:129) They contain acid that can burn you. (cid:129) They contain gas that can explode or ignite. (cid:129) They contain enough electricity to burn you. If you do not follow these steps exactly, some or all of these things can hurt you.

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Ignoring these steps could result in costly

Notice: damage to the vehicle that would not be covered by the warranty. Trying to start the vehicle by pushing or pulling it will not work, and it could damage the vehicle. 1. Check the other vehicle. It must have a 12-volt

battery with a negative ground system.

If the other vehicle’s system is not a 12-volt

Notice: system with a negative ground, both vehicles can be damaged. Only use vehicles with 12-volt systems with negative grounds to jump start your vehicle. 2. If you have a vehicle with a diesel engine with two

batteries, you should know before you begin that, especially in cold weather, you may not be able to get enough power from a single battery in another vehicle to start your diesel engine. If your vehicle has more than one battery, use the battery that is closer to the starter -- this will reduce electrical resistance. This is located on the passenger side, in the rear of the engine compartment.

3. Get the vehicles close enough so the jumper cables can reach, but be sure the vehicles are not touching each other. If they are, it could cause an unwanted ground connection. You would not be able to start your vehicle, and the bad grounding could damage the electrical systems. To avoid the possibility of the vehicles rolling, set the parking brake firmly on both vehicles involved in the jump start procedure. Put the automatic transmission in P (Park) or a manual transmission in Neutral before setting the parking brake. If you have a four-wheel-drive vehicle, be sure the transfer case is in a drive gear, not in Neutral.

If you leave the radio or other accessories

Notice: on during the jump starting procedure, they could be damaged. The repairs would not be covered by the warranty. Always turn off the radio and other accessories when jump starting the vehicle. 4. Turn off the ignition on both vehicles. Unplug

unnecessary accessories plugged into the cigarette lighter or the accessory power outlets. Turn off the radio and all the lamps that are not needed. This will avoid sparks and help save both batteries. And it could save the radio!

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5. Open the hood on the other vehicle and locate the positive (+) and negative (−) terminal locations on that vehicle. The positive (+) terminal, is located under a red plastic cover at the positive battery post. To uncover the positive (+) terminal, open the red plastic cover.

The remote negative (−) terminal is a stud located on the right front passenger side of the engine, where the negative battery cable attaches. See Engine Compartment Overview on page 5-16.

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{ CAUTION:

An electric fan can start up even when the engine is not running and can injure you. Keep hands, clothing and tools away from any underhood electric fan.

{ CAUTION:

Using a match near a battery can cause battery gas to explode. People have been hurt doing this, and some have been blinded. Use a flashlight if you need more light. Be sure the battery has enough water. You do not need to add water to the battery installed in your new vehicle. But if a battery has filler caps, be sure the right amount of fluid is there. If it is low, add water to take care of that first. If you do not, explosive gas could be present. Battery fluid contains acid that can burn you. Do not get it on you. If you accidentally get it in your eyes or on your skin, flush the place with water and get medical help immediately.

{ CAUTION:

Fans or other moving engine parts can injure you badly. Keep your hands away from moving parts once the engine is running.

6. Check that the jumper cables do not have loose or missing insulation. If they do, you could get a shock. The vehicles could be damaged too. Before you connect the cables, here are some basic things you should know. Positive (+) will go to positive (+) or to a remote positive (+) terminal if the vehicle has one. Negative (−) will go to a heavy, unpainted metal engine part or to a remote negative (−) terminal if the vehicle has one. Do not connect positive (+) to negative (−) or you will get a short that would damage the battery and maybe other parts too. And do not connect the negative (−) cable to the negative (−) terminal on the dead battery because this can cause sparks.

7. Connect the red

positive (+) cable to the positive (+) terminal of the vehicle with the dead battery.

5.3L engine (4.3L, 4.8L, 6.0L and 6.2L similar)

8. Do not let the other end touch metal. Connect it to the positive (+) terminal of the good battery. Use a remote positive (+) terminal if the vehicle has one.

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9. Now connect the black negative (−) cable to the negative (−) terminal of the good battery. Use a remote negative (−) terminal if the vehicle has one. Do not let the other end touch anything until the next step.

10. Connect the other end of the negative (−) cable to a heavy, unpainted metal engine part or to the remote negative (−) terminal, on the vehicle with the dead battery.

11. Start the vehicle with the good battery and run the

engine for a while.

12. Try to start the vehicle that had the dead battery.

If it will not start after a few tries, it probably needs service.

Notice: If the jumper cables are connected or removed in the wrong order, electrical shorting may occur and damage the vehicle. The repairs would not be covered by the vehicle warranty. Always connect and remove the jumper cables in the correct order, making sure that the cables do not touch each other or other metal.

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Jumper Cable Removal

A. Heavy, Unpainted Metal Engine Part or Remote

Negative (−) Terminal

B. Good Battery or Remote Positive (+) and Remote

Negative (−) Terminals

C. Dead Battery or Remote Positive (+) Terminal

To disconnect the jumper cables from both vehicles do the following: 1. Disconnect the black negative (−) cable from the

vehicle that had the bad battery.

2. Disconnect the black negative (−) cable from the

vehicle with the good battery.

3. Disconnect the red positive (+) cable from the

vehicle with the good battery.

4. Disconnect the red positive (+) cable from the other

vehicle.

5. Return the positive (+) terminal cover, to its original

position.

Rear Axle When to Check Lubricant It is not necessary to regularly check rear axle fluid unless you suspect there is a leak or you hear an unusual noise. A fluid loss could indicate a problem. Have it inspected and repaired. All axle assemblies are filled by volume of fluid during production. They are not filled to reach a certain level. When checking the fluid level on any axle, variations in the readings can be caused by factory fill differences between the minimum and the maximum fluid volume. Also, if a vehicle has just been driven before checking the fluid level, it may appear lower than normal because fluid has traveled out along the axle tubes and has not drained back to the sump area. Therefore, a reading taken five minutes after the vehicle has been driven will appear to have a lower fluid level than a vehicle that has been stationary for an hour or two. Remember that the rear axle assembly must be supported to get a true reading.

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How to Check Lubricant

2500HD with 6.0L and 6.2L

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All Other Series and Engines

To get an accurate reading, the vehicle should be on a level surface.

For all 4.3L, 4.8L and 5.3L 1500 Series applications, the proper level is 0.04 inches to 0.75 inches (1.0 mm to 19.0 mm) below the bottom of the filler hole, located on the rear axle. Add only enough fluid to reach the proper level. For all 6.0L and 6.2L 1500 Series applications, the proper level is from 0.6 inches to 1.6 inches (15 mm to 40 mm) below the bottom of the filler plug hole, located on the rear axle. Add only enough fluid to reach the proper level.

(cid:129) (cid:129) For all 6.0L and 6.2L 2500HD Series applications, the proper level is from 0 to 0.5 inches (0 mm to 13 mm) below the bottom of the filler plug hole, located on the rear axle. Add only enough fluid to reach the proper level. For all 6.6L DURAMAX DIESEL 2500HD Series applications and all 3500 Series applications, the proper level is from 0.6 inches to 0.8 inches (17 mm to 21 mm) below the bottom of the filler plug hole, located on the rear axle. Add only enough fluid to reach the proper level.

What to Use Refer to the Maintenance Schedule to determine what kind of lubricant to use. See Recommended Fluids and Lubricants on page 6-15.

Four-Wheel Drive Lubricant checks in this section also apply to these vehicles. Transfer Case When to Check Lubricant It is not necessary to regularly check transfer case fluid unless you suspect there is a leak, or you hear an unusual noise. A fluid loss could indicate a problem. Have it inspected and repaired.

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(cid:129) (cid:129) How to Check Lubricant

Electric Shift Transfer Case

A. Fill Plug B. Drain Plug

Manual Shift Transfer Case

A. Fill Plug B. Drain Plug

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Active Transfer Case

A. Fill Plug B. Drain Plug To get an accurate reading, the vehicle should be on a level surface.

If the level is below the bottom of the filler plug hole, located on the transfer case, you will need to add some lubricant. Add enough lubricant to raise the level to the bottom of the filler plug hole. Use care not to overtighten the plug. When to Change Lubricant Refer to the Maintenance Schedule to determine how often to change the lubricant. See Scheduled Maintenance (Gasoline Engine) on page 6-4. What to Use Refer to the Maintenance Schedule to determine what kind of lubricant to use. See Recommended Fluids and Lubricants on page 6-15.

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Front Axle When to Check and Change Lubricant It is not necessary to regularly check front axle fluid unless you suspect there is a leak or you hear an unusual noise. A fluid loss could indicate a problem. Have it inspected and repaired. How to Check Lubricant To get an accurate reading, the vehicle should be on a level surface.

All except 1500 Series

A: Fill Plug B: Drain Plug (cid:129) When the differential is cold, add enough lubricant

to raise the level from 0 (0 mm) to 1/8 inch (3.2 mm) below the filler plug hole.

(cid:129) When the differential is at operating temperature

(warm), add enough lubricant to raise the level to the bottom of the filler plug hole.

1500 Series

A: Fill Plug B: Drain Plug

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What to Use Refer to the Maintenance Schedule to determine what kind of lubricant to use. See Recommended Fluids and Lubricants on page 6-15.

Noise Control System

Tampering with Noise Control System Prohibited The following information relates to compliance with federal noise emission standards for vehicles with a Gross Vehicle Weight Rating (GVWR) of more than 10,000 lbs (4 536 kg). The Maintenance Schedule provides information on maintaining the noise control system to minimize degradation of the noise emission control system during the life of your vehicle. The noise control system warranty is given in your warranty booklet. These standards apply only to vehicles sold in the United States. Federal law prohibits the following acts or the causing thereof: 1. The removal or rendering inoperative by any

person, other than for purposes of maintenance, repair or replacement, of any device or element of design incorporated into any new vehicle for the purpose of noise control, prior to its sale or delivery to the ultimate purchaser or while it is in use; or

2. The use of the vehicle after such device or element of design has been removed or rendered inoperative by any person.

Among those acts presumed to constitute tampering are the acts listed below. Insulation: (cid:129) Removal of the noise shields or any underhood

insulation.

Engine: (cid:129) Removal or rendering engine speed governor, if the

vehicle has one, inoperative so as to allow engine speed to exceed manufacturer specifications.

Fan and Drive: (cid:129) Removal of fan clutch, if the vehicle has one, or

rendering clutch inoperative.

(cid:129) Removal of the fan shroud, if the vehicle has one. Air Intake: (cid:129) Removal of the air cleaner silencer. (cid:129) Modification of the air cleaner. Exhaust: (cid:129) Removal of the muffler and/or resonator. (cid:129) Removal of the exhaust pipes and exhaust pipe

clamps.

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Headlamp Aiming The vehicle has a visual optical headlamp aiming system. The aim of the headlamps have been preset at the factory and should need no further adjustment. However, if the vehicle is damaged in a crash, the aim of the headlamps may be affected and adjustment may be necessary. If oncoming vehicles flash their high beams at you, this may mean the vertical aim of your headlamps needs to be adjusted. It is recommended that the vehicle is taken to your dealer/retailer for service if the headlamps need to be adjusted. It is possible however, to re-aim the headlamps as described.

The vehicle should: (cid:129) Be placed so the headlamps are 25 ft. (7.6 m) from

a light colored wall.

(cid:129) Have all four tires on a level surface which is level

all the way to the wall.

(cid:129) Be placed so it is perpendicular to the wall. (cid:129) Not have any snow, ice, or mud on it. (cid:129) Be fully assembled and all other work stopped while

headlamp aiming is being performed.

(cid:129) Normally loaded with a full tank of fuel and one

person or 160 lbs (75 kg) sitting on the driver seat.

(cid:129) Have the tires properly inflated. (cid:129) Have the spare tire is in its proper location in the

vehicle.

Headlamp aiming is done with the vehicle’s low-beam headlamps. The high-beam headlamps will be correctly aimed if the low-beam headlamps are aimed properly.

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To adjust the vertical aim: 1. Open the hood. See Hood Release on page 5-14

for more information.

2. Locate the aim dot on the lens of the low-beam

headlamp.

3. Record the distance from the ground to the aim dot

on the low-beam headlamp.

4. At a wall, measure from the ground upward (A) to

the recorded distance from Step 3 and mark it.

5. Draw or tape a horizontal line (B) on the wall the

width of the vehicle at the height of the mark in Step 4.

Notice: Do not cover a headlamp to improve beam cut-off when aiming. Covering a headlamp may cause excessive heat build-up which may cause damage to the headlamp. 6. Turn on the low-beam headlamps and place a piece of cardboard or equivalent in front of the headlamp not being adjusted. This allows only the beam of light from the headlamp being adjusted to be seen on the flat surface.

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9. Make sure that the light from the headlamp is

positioned at the bottom edge of the horizontal tape line. The lamp on the left (A) shows the correct headlamp aim. The lamp on the right (B) shows the incorrect headlamp aim.

10. Repeat Steps 7 through 9 for the opposite

headlamp.

7. Locate the vertical headlamp aiming screws, which are under the hood near each headlamp assembly. The adjustment screw can be turned with a E8 Torx® socket.

8. Turn the vertical aiming screw until the headlamp beam is aimed to the horizontal tape line. Turn it clockwise or counterclockwise to raise or lower the angle of the beam.

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Bulb Replacement For the proper type of replacement bulbs, see Replacement Bulbs on page 5-66. For any bulb changing procedure not listed in this section, contact your dealer/retailer.

Halogen Bulbs

{ CAUTION:

Halogen bulbs have pressurized gas inside and can burst if you drop or scratch the bulb. You or others could be injured. Be sure to read and follow the instructions on the bulb package.

Headlamps To replace one of these bulbs: 1. Open the hood. See Hood Release on page 5-14

for more information.

2. If you are replacing the bulb on the passenger side remove the Engine Air Cleaner cover. See Engine Air Cleaner/Filter on page 5-22 for more information.

3. Reach in and access the bulb sockets from inside

the engine compartment.

4. Turn the bulb socket counterclockwise to remove it from the headlamp assembly and pull it straight out. 5. Unplug the electrical connector from the old bulb by

releasing the clips on the bulb socket.

6. Replace it with a new bulb socket. 7. Plug in the electrical connector to the new bulb

socket.

8. Reinstall the new bulb socket into the headlamp

assembly and turn it clockwise to secure.

9. Close the hood.

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Center High-Mounted Stoplamp (CHMSL) and Cargo Lamp To replace one of these bulbs:

1. Remove the screws and lift off the lamp assembly.

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A. Cargo Lamp B. Center High-Mounted Stoplamp Bulb (CHMSL)

2. Remove the bulbs by turning socket

counterclockwise and pulling the bulb straight out. 3. Install the bulbs by pushing the bulb straight in and

turning clockwise.

4. Reinstall the lamp assembly and tighten the screws.

Pickup Box Identification and Fender Marker Lamps To replace a pickup box identification or fender marker lamp bulb: 1. Press the tab from the back to remove the lamp. 2. Unplug the lamp assembly harness. 3. Gently pry the individual lamp from the lamp

assembly.

4. Unplug the lamp. 5. Plug in a new lamp and snap it into the assembly. 6. Reinstall the lamp assembly.

Taillamps, Turn Signal, Stoplamps and Back-up Lamps To replace one of these bulbs: 1. Open the tailgate. Tailgate on page 2-13 for more

information.

2. Remove the two rear

lamp assembly screws near the tailgate latch strikerpost and pull out the lamp assembly.

3. Determine which of the following taillamp

assemblies applies to your vehicle.

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Dually Models

All Other Models

A. Stoplamp/Taillamp/Turn Signal Lamp B. Back-up Lamp C. Stoplamp/Taillamp/Turn Signal Lamp

4. Press the tab, if the vehicle has one, and turn the bulb socket counterclockwise to remove it from the taillamp assembly.

A. Stoplamp/Taillamp/Turn Signal Lamp B. Stoplamp/Taillamp/Turn Signal Lamp C. Back-up Lamp D. Sidemarker Lamp

5. Pull the old bulb straight out from the socket. 6. Press a new bulb into the socket and turn the socket

clockwise into the taillamp assembly.

7. Reinstall the taillamp assembly.

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Taillamps (Chassis Cab Models)

License Plate Lamp To replace one of these bulbs: 1. Reach under the rear bumper for the bulb socket.

A. Backup Lamp B. Stoplamp/Taillamp/Turn Signal Lamp To replace one of these bulbs: 1. Remove the four screws. 2. Lift the lens off the lamp assembly. 3. Turn the old bulb counterclockwise and pull the it

straight out from the socket.

4. Install a new bulb into the socket, turn it clockwise,

and press it in until it is tight.

5. Reinstall the lens and the four screws.

2. Turn the bulb socket counterclockwise and pull the

bulb socket out of the connector.

3. Pull the old bulb from the bulb socket, keeping the

bulb straight as you pull it out.

4. Install the new bulb. 5. Reverse Steps 1 through 3 to reinstall the bulb

socket.

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Replacement Bulbs

Exterior Lamp

Bulb Number

Back-up Lamp

Back-up Lamp*

Cargo Lamp and Center High-Mounted Stoplamp (CHMSL)

Fender Marker

High-Beam Headlamp

Low-Beam Headlamp

License Plate Lamp

Stoplamp/Taillamp/ Turn Signal Lamp

Sidemarker Lamp

Stoplamp/Turn Signal Lamp/Taillamp*

* Chassis Cab Models

3047

1156

912

W5WLL

9005

H11

168

3047

194

1157

For replacement bulbs not listed here, contact your dealer/retailer.

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Windshield Wiper Blade Replacement Windshield wiper blades should be inspected for wear or cracking. See Scheduled Maintenance (Gasoline Engine) on page 6-4 for more information on wiper blade inspection. Replacement blades come in different types and are removed in different ways. Here is how to remove the wiper blade: 1. Pull the windshield wiper arm connector away from

the windshield.

2. Squeeze the grooved areas on each side of the

blade and turn the blade assembly away from the arm connector.

3. Install the new blade onto the arm connector and make sure the grooved areas are fully set in the locked position.

For the proper type and size, see Maintenance Replacement Parts on page 6-17. Tires Your new vehicle comes with high-quality tires made by a leading tire manufacturer. If you ever have questions about your tire warranty and where to obtain service, see your vehicle Warranty booklet for details. For additional information refer to the tire manufacturer.

{ CAUTION:

Poorly maintained and improperly used tires are dangerous.

(cid:129) Overloading your vehicle’s tires can cause overheating as a result of too much flexing. You could have an air-out and a serious accident. See Loading the Vehicle on page 4-34.

(cid:129) Underinflated tires pose the same danger as overloaded tires. The resulting accident could cause serious injury. Check all tires frequently to maintain the recommended pressure. Tire pressure should be checked when your vehicle’s tires are cold. See Inflation - Tire Pressure on page 5-76.

(cid:129) Overinflated tires are more likely to be cut, punctured, or broken by a sudden impact — such as when you hit a pothole. Keep tires at the recommended pressure.

(cid:129) Worn, old tires can cause accidents.

If the tire’s tread is badly worn, or if your vehicle’s tires have been damaged, replace them.

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20-Inch Tires If your vehicle has the optional 20-inch P275/55R20 size tires, they are classified as touring tires and are designed for on road use. The low-profile, wide tread design is not recommended for “off-road” driving or commercial uses such as snow plowing. See Off-Road Driving on page 4-13 and Adding a Snow Plow or Similar Equipment on page 4-40 for additional information. Notice: If the vehicle has low-profile tires, they are more susceptible to damage from road hazards or curb impact than standard profile tires. Tire and/or wheel assembly damage can occur when coming into contact with road hazards like, potholes, or sharp edged objects, or when sliding into a curb. The vehicle warranty does not cover this type of damage. Keep tires set to the correct inflation pressure and, when possible avoid contact with curbs, potholes, and other road hazards.

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Tire Sidewall Labeling Useful information about a tire is molded into the sidewall. The following illustrations are examples of a typical P-Metric and a LT-Metric tire sidewall.

Passenger (P-Metric) Tire

(A) Tire Size: The tire size code is a combination of letters and numbers used to define a particular tire’s width, height, aspect ratio, construction type, and service description. See the “Tire Size” illustration later in this section for more detail.

(B) TPC Spec (Tire Performance Criteria Specification): Original equipment tires designed to GM’s specific tire performance criteria have a TPC specification code molded onto the sidewall. GM’s TPC specifications meet or exceed all federal safety guidelines. (C) DOT (Department of Transportation): The Department of Transportation (DOT) code indicates that the tire is in compliance with the U.S. Department of Transportation Motor Vehicle Safety Standards. (D) Tire Identification Number (TIN): The letters and numbers following DOT code are the Tire Identification Number (TIN). The TIN shows the manufacturer and plant code, tire size, and date the tire was manufactured. The TIN is molded onto both sides of the tire, although only one side may have the date of manufacture.

(E) Tire Ply Material: The type of cord and number of plies in the sidewall and under the tread. (F) Uniform Tire Quality Grading (UTQG): Tire manufacturers are required to grade tires based on three performance factors: treadwear, traction, and temperature resistance. For more information, see Uniform Tire Quality Grading on page 5-89. (G) Maximum Cold Inflation Load Limit: Maximum load that can be carried and the maximum pressure needed to support that load. For information on recommended tire pressure see Inflation - Tire Pressure on page 5-76 and Loading the Vehicle on page 4-34.

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(B) TPC Spec (Tire Performance Criteria Specification): Original equipment tires designed to GM’s specific tire performance criteria have a TPC specification code molded onto the sidewall. GM’s TPC specifications meet or exceed all federal safety guidelines. (C) Dual Tire Maximum Load: Maximum load that can be carried and the maximum pressure needed to support that load when used in a dual configuration. For information on recommended tire pressure see Inflation - Tire Pressure on page 5-76 and Loading the Vehicle on page 4-34. (D) DOT (Department of Transportation): The Department of Transportation (DOT) code indicates that the tire is in compliance with the U.S. Department of Transportation Motor Vehicle Safety Standards. (E) Tire Identification Number (TIN): The letters and numbers following DOT code are the Tire Identification Number (TIN). The TIN shows the manufacturer and plant code, tire size, and date the tire was manufactured. The TIN is molded onto both sides of the tire, although only one side may have the date of manufacture.

Light Truck (LT-Metric) Tire

(A) Tire Size: The tire size code is a combination of letters and numbers used to define a particular tire’s width, height, aspect ratio, construction type, and service description. See the “Tire Size” illustration later in this section for more detail.

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(F) Tire Ply Material: The type of cord and number of plies in the sidewall and under the tread. (G) Single Tire Maximum Load: Maximum load that can be carried and the maximum pressure needed to support that load when used as a single. For information on recommended tire pressure see Inflation - Tire Pressure on page 5-76 and Loading the Vehicle on page 4-34. Tire Size The following examples show the different parts of a tire size.

Passenger (P-Metric) Tire

(A) Passenger (P-Metric) Tire: The United States version of a metric tire sizing system. The letter P as the first character in the tire size means a passenger vehicle tire engineered to standards set by the U.S. Tire and Rim Association.

(B) Tire Width: The three-digit number indicates the tire section width in millimeters from sidewall to sidewall. (C) Aspect Ratio: A two-digit number that indicates the tire height-to-width measurements. For example, if the tire size aspect ratio is 75, as shown in item C of the tire illustration, it would mean that the tire’s sidewall is 75 percent as high as it is wide. (D) Construction Code: A letter code is used to indicate the type of ply construction in the tire. The letter R means radial ply construction; the letter D means diagonal or bias ply construction; and the letter B means belted-bias ply construction. (E) Rim Diameter: Diameter of the wheel in inches. (F) Service Description: These characters represent the load index and speed rating of the tire. The load index represents the load carry capacity a tire is certified to carry. The speed rating is the maximum speed a tire is certified to carry a load.

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(D) Construction Code: A letter code is used to indicate the type of ply construction in the tire. The letter R means radial ply construction; the letter D means diagonal or bias ply construction; and the letter B means belted-bias ply construction. (E) Rim Diameter: Diameter of the wheel in inches. (F) Load Range : Load Range. (G) Service Description: The service description indicates the load index and speed rating of a tire. If two numbers are given as in the example, 120/116, then this represents the load index for single versus dual wheel usage (single/dual). The speed rating is the maximum speed a tire is certified to carry a load.

Light Truck (LT-Metric) Tire

(A) Light Truck (LT-Metric) Tire: The United States version of a metric tire sizing system. The letters LT as the first two characters in the tire size means a light truck tire engineered to standards set by the U.S. Tire and Rim Association. (B) Tire Width: The three-digit number indicates the tire section width in millimeters from sidewall to sidewall. (C) Aspect Ratio: A two-digit number that indicates the tire height-to-width measurements. For example, if the tire size aspect ratio is 75, as shown in item C of the light truck (LT-Metric) tire illustration, it would mean that the tire’s sidewall is 75 percent as high as it is wide.

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Tire Terminology and Definitions

Air Pressure: The amount of air inside the tire pressing outward on each square inch of the tire. Air pressure is expressed in pounds per square inch (psi) or kilopascal (kPa). Accessory Weight: This means the combined weight of optional accessories. Some examples of optional accessories are, automatic transmission, power steering, power brakes, power windows, power seats, and air conditioning. Aspect Ratio: The relationship of a tire’s height to its width. Belt: A rubber coated layer of cords that is located between the plies and the tread. Cords may be made from steel or other reinforcing materials. Bead: The tire bead contains steel wires wrapped by steel cords that hold the tire onto the rim. Bias Ply Tire: A pneumatic tire in which the plies are laid at alternate angles less than 90 degrees to the centerline of the tread.

Cold Tire Pressure: The amount of air pressure in a tire, measured in pounds per square inch (psi) or kilopascals (kPa) before a tire has built up heat from driving. See Inflation - Tire Pressure on page 5-76. Curb Weight: The weight of a motor vehicle with standard and optional equipment including the maximum capacity of fuel, oil, and coolant, but without passengers and cargo. DOT Markings: A code molded into the sidewall of a tire signifying that the tire is in compliance with the U.S. Department of Transportation (DOT) motor vehicle safety standards. The DOT code includes the Tire Identification Number (TIN), an alphanumeric designator which can also identify the tire manufacturer, production plant, brand, and date of production. GVWR: Gross Vehicle Weight Rating. See Loading the Vehicle on page 4-34. GAWR FRT: Gross Axle Weight Rating for the front axle. See Loading the Vehicle on page 4-34. GAWR RR: Gross Axle Weight Rating for the rear axle. See Loading the Vehicle on page 4-34.

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Intended Outboard Sidewall: The side of an asymmetrical tire, that must always face outward when mounted on a vehicle. Kilopascal (kPa): The metric unit for air pressure. Light Truck (LT-Metric) Tire: A tire used on light duty trucks and some multipurpose passenger vehicles. Load Index: An assigned number ranging from 1 to 279 that corresponds to the load carrying capacity of a tire. Maximum Inflation Pressure: The maximum air pressure to which a cold tire can be inflated. The maximum air pressure is molded onto the sidewall. Maximum Load Rating: The load rating for a tire at the maximum permissible inflation pressure for that tire. Maximum Loaded Vehicle Weight: The sum of curb weight, accessory weight, vehicle capacity weight, and production options weight.

Normal Occupant Weight: The number of occupants a vehicle is designed to seat multiplied by 150 lbs (68 kg). See Loading the Vehicle on page 4-34. Occupant Distribution: Designated seating positions. Outward Facing Sidewall: The side of an asymmetrical tire that has a particular side that faces outward when mounted on a vehicle. The side of the tire that contains a whitewall, bears white lettering, or bears manufacturer, brand, and/or model name molding that is higher or deeper than the same moldings on the other sidewall of the tire. Passenger (P-Metric) Tire: A tire used on passenger cars and some light duty trucks and multipurpose vehicles. Recommended Inflation Pressure: Vehicle manufacturer’s recommended tire inflation pressure as shown on the tire placard. See Inflation - Tire Pressure on page 5-76 and Loading the Vehicle on page 4-34.

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Radial Ply Tire: A pneumatic tire in which the ply cords that extend to the beads are laid at 90 degrees to the centerline of the tread. Rim: A metal support for a tire and upon which the tire beads are seated. Sidewall: The portion of a tire between the tread and the bead. Speed Rating: An alphanumeric code assigned to a tire indicating the maximum speed at which a tire can operate. Traction: The friction between the tire and the road surface. The amount of grip provided. Tread: The portion of a tire that comes into contact with the road. Treadwear Indicators: Narrow bands, sometimes called wear bars, that show across the tread of a tire when only 1/16 inch (1.6 mm) of tread remains. See When It Is Time for New Tires on page 5-86.

UTQGS (Uniform Tire Quality Grading Standards): A tire information system that provides consumers with ratings for a tire’s traction, temperature, and treadwear. Ratings are determined by tire manufacturers using government testing procedures. The ratings are molded into the sidewall of the tire. See Uniform Tire Quality Grading on page 5-89. Vehicle Capacity Weight: The number of designated seating positions multiplied by 150 lbs (68 kg) plus the rated cargo load. See Loading the Vehicle on page 4-34. Vehicle Maximum Load on the Tire: Load on an individual tire due to curb weight, accessory weight, occupant weight, and cargo weight. Vehicle Placard: A label permanently attached to a vehicle showing the vehicle’s capacity weight and the original equipment tire size and recommended inflation pressure. See “Tire and Loading Information Label” under Loading the Vehicle on page 4-34.

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Inflation - Tire Pressure Tires need the correct amount of air pressure to operate effectively. Notice: Do not let anyone tell you that under-inflation or over-inflation is all right. It is not. If your tires do not have enough air (under-inflation), you can get the following: (cid:129) Too much flexing (cid:129) Too much heat (cid:129) Tire overloading (cid:129) Premature or irregular wear (cid:129) Poor handling (cid:129) Reduced fuel economy If your tires have too much air (over-inflation), you can get the following: (cid:129) Unusual wear (cid:129) Poor handling (cid:129) Rough ride (cid:129) Needless damage from road hazards

A vehicle specific Tire and Loading Information label is attached to your vehicle. This label shows your vehicle’s original equipment tires and the correct inflation pressures for your tires when they are cold. The recommended cold tire inflation pressure, shown on the label, is the minimum amount of air pressure needed to support your vehicle’s maximum load carrying capacity. For additional information regarding how much weight your vehicle can carry, and an example of the Tire and Loading Information label, see Loading the Vehicle on page 4-34. How you load your vehicle affects vehicle handling and ride comfort. Never load your vehicle with more weight than it was designed to carry. When to Check Check your tires once a month or more. Do not forget to check the pressure of the spare tire, if your vehicle has one. See Spare Tire on page 5-114 for additional information.

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How to Check Use a good quality pocket-type gage to check tire pressure. You cannot tell if your tires are properly inflated simply by looking at them. Radial tires may look properly inflated even when they’re underinflated. Check the tire’s inflation pressure when the tires are cold. Cold means your vehicle has been sitting for at least three hours or driven no more than 1 mile (1.6 km). Remove the valve cap from the tire valve stem. Press the tire gage firmly onto the valve to get a pressure measurement. If the cold tire inflation pressure matches the recommended pressure on the tire and loading information label, no further adjustment is necessary. If the pressure is low, add air until you reach the recommended amount. If you overfill the tire, release air by pushing on the metal stem in the center of the tire valve. Recheck the tire pressure with the tire gage. Be sure to put the valve caps back on the valve stems. They help prevent leaks by keeping out dirt and moisture.

High-Speed Operation

{ CAUTION:

Driving at high speeds, 100 mph (160 km/h) or higher, puts an additional strain on tires. Sustained high-speed driving causes excessive heat build up and can cause sudden tire failure. You could have a crash and you or others could be killed. Some high-speed rated tires require inflation pressure adjustment for high speed operation. When speed limits and road conditions are such that a vehicle can be driven at high speeds, make sure the tires are rated for high speed operation, in excellent condition, and set to the correct cold tire inflation pressure for the vehicle load.

Vehicles with P265/70R17 or P275/55R20 size tires require inflation pressure adjustment when driving the vehicle at speeds of 100 mph (160 km/h) or higher. Set the cold tire inflation pressure to 3 psi (20 kPa) above the recommended cold tire pressure shown on the Tire and Loading Information label.

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When you end this high-speed driving, return the tires to the cold inflation pressure shown on the Tire and Loading Information label. See Loading the Vehicle on page 4-34 and Inflation - Tire Pressure on page 5-76.

Dual Tire Operation When the vehicle is new, or whenever a wheel, wheel bolt or wheel nut is replaced, check the wheel nut torque after 100, 1,000 and 6,000 miles (160, 1 600 and 10 000 km) of driving. For proper torque and wheel nut tightening information, see Removing the Spare Tire and Tools on page 5-95. The outer tire on a dual wheel setup generally wears faster than the inner tire. Your tires will wear more evenly and last longer if you rotate the tires periodically, see Tire Inspection and Rotation on page 5-84. Also see Scheduled Maintenance (Gasoline Engine) on page 6-4.

{ CAUTION:

If you operate your vehicle with a tire that is badly underinflated, the tire can overheat. An overheated tire can lose air suddenly or catch fire. You or others could be injured. Be sure all tires (including the spare) are properly inflated.

See Inflation - Tire Pressure on page 5-76, for information on proper tire inflation.

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Tire Pressure Monitor System The Tire Pressure Monitor System (TPMS) uses radio and sensor technology to check tire pressure levels. The TPMS sensors monitor the air pressure in your vehicle’s tires and transmit tire pressure readings to a receiver located in the vehicle. Each tire, including the spare (if provided), should be checked monthly when cold and inflated to the inflation pressure recommended by the vehicle manufacturer on the vehicle placard or tire inflation pressure label. (If your vehicle has tires of a different size than the size indicated on the vehicle placard or tire inflation pressure label, you should determine the proper tire inflation pressure for those tires.) As an added safety feature, your vehicle has been equipped with a tire pressure monitoring system (TPMS) that illuminates a low tire pressure telltale when one or more of your tires is significantly under-inflated. Accordingly, when the low tire pressure telltale illuminates, you should stop and check your tires as soon as possible, and inflate them to the proper pressure. Driving on a significantly under-inflated tire causes the tire to overheat and can lead to tire failure. Under-inflation also reduces fuel efficiency and tire tread life, and may affect the vehicle’s handling and stopping ability.

Please note that the TPMS is not a substitute for proper tire maintenance, and it is the driver’s responsibility to maintain correct tire pressure, even if under-inflation has not reached the level to trigger illumination of the TPMS low tire pressure telltale. Your vehicle has also been equipped with a TPMS malfunction indicator to indicate when the system is not operating properly. The TPMS malfunction indicator is combined with the low tire pressure telltale. When the system detects a malfunction, the telltale will flash for approximately one minute and then remain continuously illuminated. This sequence will continue upon subsequent vehicle start-ups as long as the malfunction exists. When the malfunction indicator is illuminated, the system may not be able to detect or signal low tire pressure as intended. TPMS malfunctions may occur for a variety of reasons, including the installation of replacement or alternate tires or wheels on the vehicle that prevent the TPMS from functioning properly. Always check the TPMS malfunction telltale after replacing one or more tires or wheels on your vehicle to ensure that the replacement or alternate tires and wheels allow the TPMS to continue to function properly. See Tire Pressure Monitor Operation on page 5-80 for additional information.

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Federal Communications Commission (FCC) and Industry and Science Canada The Tire Pressure Monitor System (TPMS) operates on a radio frequency and complies with Part 15 of the FCC Rules. Operation is subject to the following two conditions: 1. This device may not cause harmful interference. 2. This device must accept any interference received,

including interference that may cause undesired operation.

Vehicles with TPMS operate on a radio frequency and comply with RSS-210 of Industry and Science Canada. Operation is subject to the following two conditions: 1. This device may not cause interference. 2. This device must accept any interference received,

including interference that may cause undesired operation of the device.

Changes or modifications to this system by other than an authorized service facility could void authorization to use this equipment.

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Tire Pressure Monitor Operation This vehicle may have a Tire Pressure Monitor System (TPMS). The TPMS is designed to warn the driver when a low tire pressure condition exists. TPMS sensors are mounted onto each tire and wheel assembly, excluding the spare tire and wheel assembly. The TPMS sensors monitor the air pressure in the vehicle’s tires and transmits the tire pressure readings to a receiver located in the vehicle.

When a low tire pressure condition is detected, the TPMS will illuminate the low tire pressure warning symbol located on the instrument panel cluster.

At the same time a message to check the pressure in a specific tire appears on the Driver Information Center (DIC) display. The low tire pressure warning light and the DIC warning message come on at each ignition cycle until the tires are inflated to the correct inflation pressure. If your vehicle has DIC buttons, tire pressure levels can be viewed by the driver. For additional information and details about the DIC operation and displays see DIC Operation and Displays (With DIC Buttons) on page 3-53
or DIC Operation and Displays (Without DIC Buttons) on page 3-59 and DIC Warnings and Messages on page 3-66.

The low tire pressure warning light may come on in cool weather when the vehicle is first started, and then turn off as you start to drive. This could be an early indicator that the air pressure in the tire(s) are getting low and need to be inflated to the proper pressure. A Tire and Loading Information label, attached to your vehicle, shows the size of your vehicle’s original equipment tires and the correct inflation pressure for your vehicle’s tires when they are cold. See Loading the Vehicle on page 4-34, for an example of the Tire and Loading Information label and its location on your vehicle. Also see Inflation - Tire Pressure on page 5-76. Your vehicle’s TPMS can warn you about a low tire pressure condition but it does not replace normal tire maintenance. See Tire Inspection and Rotation on page 5-84 and Tires on page 5-67. Notice: Liquid tire sealants could damage the Tire Pressure Monitor System (TPMS) sensors. Sensor damage caused by using a tire sealant is not covered by your warranty. Do not use liquid tire sealants.

TPMS Malfunction Light and Message The TPMS will not function properly if one or more of the TPMS sensors are missing or inoperable. When the system detects a malfunction, the low tire warning light flashes for about one minute and then stays on for the remainder of the ignition cycle. A DIC warning message is also displayed. The low tire warning light and DIC warning message come on at each ignition cycle until the problem is corrected. Some of the conditions that can cause the malfunction light and DIC message to come on are: (cid:129) One of the road tires has been replaced with the spare tire. The spare tire does not have a TPMS sensor. The TPMS malfunction light and DIC message should go off once you re-install the road tire containing the TPMS sensor. The TPMS sensor matching process was started but not completed or not completed successfully after rotating the vehicle’s tires. The DIC message and TPMS malfunction light should go off once the TPMS sensor matching process is performed successfully. See “TPMS Sensor Matching Process” later in this section.

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(cid:129) (cid:129) One or more TPMS sensors are missing or damaged. The DIC message and the TPMS malfunction light should go off when the TPMS sensors are installed and the sensor matching process is performed successfully. See your dealer/retailer for service.

(cid:129) Replacement tires or wheels do not match your

vehicle’s original equipment tires or wheels. Tires and wheels other than those recommended for your vehicle could prevent the TPMS from functioning properly. See Buying New Tires on page 5-86.

(cid:129) Operating electronic devices or being near facilities using radio wave frequencies similar to the TPMS could cause the TPMS sensors to malfunction.

If the TPMS is not functioning it cannot detect or signal a low tire condition. See your dealer/retailer for service if the TPMS malfunction light and DIC message comes on and stays on.

TPMS Sensor Matching Process Each TPMS sensor has a unique identification code. Any time you rotate your vehicle’s tires or replace one or more of the TPMS sensors, the identification codes will need to be matched to the new tire/wheel position. The sensors are matched to the tire/wheel positions in the following order: driver side front tire, passenger side front tire, passenger side rear tire, and driver side rear tire using a TPMS diagnostic tool. See your dealer/retailer for service. The TPMS sensors can also be matched to each tire/wheel position by increasing or decreasing the tire’s air pressure. If increasing the tire’s air pressure, do not exceed the maximum inflation pressure indicated on the tire’s sidewall. To decrease air-pressure out of a tire you can use the pointed end of the valve cap, a pencil-style air pressure gage, or a key. You have two minutes to match the first tire/wheel position, and five minutes overall to match all four tire/wheel positions. If it takes longer than two minutes, to match the first tire and wheel, or more than five minutes to match all four tire and wheel positions the matching process stops and you need to start over.

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The TPMS sensor matching process is outlined below: 1. Set the parking brake. 2. Turn the ignition switch to ON/RUN with the

engine off.

3. Press the Remote Keyless Entry (RKE) transmitter’s

LOCK and UNLOCK buttons at the same time for approximately five seconds. The horn sounds twice to signal the receiver is in relearn mode and TIRE LEARNING ACTIVE message displays on the DIC screen. If your vehicle does not have RKE, press the Driver Information Center (DIC) vehicle information button until the PRESS V TO RELEARN TIRE POSITIONS message displays. The horn sounds twice to signal the receiver is in relearn mode and TIRE LEARNING ACTIVE message displays on the DIC screen. If your vehicle does not have RKE or DIC buttons, press the trip odometer reset stem located on the instrument panel cluster until the PRESS V TO RELEARN TIRE POSITIONS message displays. The horn sounds twice to signal the receiver is in relearn mode and TIRE LEARNING ACTIVE message displays on the DIC screen.

4. Start with the driver side front tire.

5. Remove the valve cap from the valve cap stem.

Activate the TPMS sensor by increasing or decreasing the tire’s air pressure for five seconds, or until a horn chirp sounds. The horn chirp, which may take up to 30 seconds to sound, confirms that the sensor identification code has been matched to this tire and wheel position.

6. Proceed to the passenger side front tire, and repeat

the procedure in Step 5.

7. Proceed to the passenger side rear tire, and repeat

the procedure in Step 5.

8. Proceed to the driver side rear tire, and repeat the

procedure in Step 5. The horn sounds two times to indicate the sensor identification code has been matched to the driver side rear tire, and that the TPMS sensor matching process is no longer active. The TIRE LEARNING ACTIVE message on the DIC display screen goes off.

9. Turn the ignition switch to LOCK/OFF. 10. Set all four tires to the recommended air pressure

level as indicated on the Tire and Loading Information label.

11. Put the valve caps back on the valve stems.

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Tire Inspection and Rotation We recommend that you regularly inspect your vehicle’s tires, including the spare tire, for signs of wear or damage. See When It Is Time for New Tires on page 5-86 for more information. Tires should be rotated every 5,000 to 8,000 miles (8 000 to 13 000 km). See Scheduled Maintenance (Gasoline Engine) on page 6-4. The purpose of a regular tire rotation is to achieve a uniform wear for all tires on the vehicle. This will ensure that your vehicle continues to perform most like it did when the tires were new. Any time you notice unusual wear, rotate your tires as soon as possible and check wheel alignment. Also check for damaged tires or wheels. See When It Is Time for New Tires on page 5-86 and Wheel Replacement on page 5-90. If your vehicle has dual rear wheels, also see Dual Tire Operation on page 5-78.

If your vehicle has single rear wheels and the tread design for the front tires is the same as the rear tires, use the rotation pattern shown here when rotating the tires.

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If your vehicle has dual rear wheels and the tread design for the front tires is the same as the rear tires, always use one of the correct rotation patterns shown here when rotating the tires.

If your vehicle has dual rear wheels and the tread design for the front tires is different from the dual rear tires, always use the correct rotation pattern shown here when rotating the tires.

The dual tires are rotated as a pair, and the inside rear tires become the outside rear tires. When you install dual wheels, be sure the vent holes in the inner and outer wheels on each side are lined up. After the tires have been rotated, adjust the front and rear inflation pressures as shown on the Tire and Loading Information label. See Inflation - Tire Pressure on page 5-76 and Loading the Vehicle on page 4-34. Make certain that all wheel nuts are properly tightened. See “Wheel Nut Torque” under Capacities and Specifications on page 5-131.

{ CAUTION:

Rust or dirt on a wheel, or on the parts to which it is fastened, can make wheel nuts become loose after time. The wheel could come off and cause an accident. When you change a wheel, remove any rust or dirt from places where the wheel attaches to the vehicle. In an emergency, you can use a cloth or a paper towel to do this; but be sure to use a scraper or wire brush later, if needed, to get all the rust or dirt off. See Changing a Flat Tire on page 5-94.

If your vehicle has a Tire Pressure Monitor System (TPMS), reset the TPMS sensors after rotating the tires. See Tire Pressure Monitor Operation on page 5-80. Make sure the spare tire, if your vehicle has one, is stored securely. Push, pull, and then try to rotate or turn the tire. If it moves, tighten the cable. See Storing a Flat or Spare Tire and Tools on page 5-110.

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When It Is Time for New Tires Various factors, such as maintenance, temperatures, driving speeds, vehicle loading, and road conditions, influence when you need new tires.

One way to tell when it is time for new tires is to check the treadwear indicators, which appear when your tires have only 1/16 inch (1.6 mm) or less of tread remaining. Some commercial truck tires may not have treadwear indicators.

You need new tires if any of the following statements are true: (cid:129) You can see the indicators at three or more places

around the tire.

(cid:129) You can see cord or fabric showing through the

tire’s rubber. The tread or sidewall is cracked, cut, or snagged deep enough to show cord or fabric.

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The tire has a bump, bulge, or split. The tire has a puncture, cut, or other damage that cannot be repaired well because of the size or location of the damage.

The rubber in tires degrades over time, even if they are not being used. This is also true for the spare tire, if your vehicle has one. Multiple conditions affect how fast this aging takes place, including temperatures, loading conditions, and inflation pressure maintenance. With proper care and maintenance tires will typically wear out before they degrade due to age. If you are unsure about the need to replace your tires as they get older, consult the tire manufacturer for more information. Buying New Tires GM has developed and matched specific tires for your vehicle. The original equipment tires installed on your vehicle, when it was new, were designed to meet General Motors Tire Performance Criteria Specification (TPC spec) system rating. If you need replacement tires, GM strongly recommends that you get tires with the same TPC Spec rating. This way, your vehicle will continue to have tires that are designed to give the same performance and vehicle safety, during normal use, as the original tires.

(cid:129) (cid:129) (cid:129) GM’s exclusive TPC Spec system considers over a dozen critical specifications that impact the overall performance of your vehicle, including brake system performance, ride and handling, traction control, and tire pressure monitoring performance. GM’s TPC Spec number is molded onto the tire’s sidewall near the tire size. If the tires have an all-season tread design, the TPC spec number will be followed by a MS, for mud and snow. See Tire Sidewall Labeling on page 5-68 for additional information. GM recommends replacing tires in sets of four (or six if your vehicle has dual rear wheels). This is because uniform tread depth on all tires will help keep your vehicle performing most like it did when the tires were new. Replacing less than a full set of tires can affect the braking and handling performance of your vehicle. See Tire Inspection and Rotation on page 5-84 for information on proper tire rotation.

{ CAUTION:

Mixing tires could cause you to lose control while driving. If you mix tires of different sizes, brands, or types (radial and bias-belted tires) the vehicle may not handle properly, and you

CAUTION:

(Continued)

CAUTION:

(Continued)

could have a crash. Using tires of different sizes, brands, or types may also cause damage to your vehicle. Be sure to use the correct size, brand, and type of tires on your vehicle’s wheels.

{ CAUTION:

If you use bias-ply tires on the vehicle, the wheel rim flanges could develop cracks after many miles of driving. A tire and/or wheel could fail suddenly, causing a crash. Use only radial-ply tires with the wheels on the vehicle.

If you must replace your vehicle’s tires with those that do not have a TPC Spec number, make sure they are the same size, load range, speed rating, and construction type (radial and bias-belted tires) as your vehicle’s original tires.

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Vehicles that have a tire pressure monitoring system could give an inaccurate low-pressure warning if non-TPC Spec rated tires are installed on your vehicle. Non-TPC Spec rated tires may give a low-pressure warning that is higher or lower than the proper warning level you would get with TPC Spec rated tires. See Tire Pressure Monitor System on page 5-79. Your vehicle’s original equipment tires are listed on the Tire and Loading Information label. See Loading the Vehicle on page 4-34, for more information about the Tire and Loading Information label and its location on your vehicle.

Different Size Tires and Wheels If you add wheels or tires that are a different size than your original equipment wheels and tires, this could affect the way your vehicle performs, including its braking, ride and handling characteristics, stability, and resistance to rollover. Additionally, if your vehicle has electronic

systems such as anti-lock brakes, rollover airbags, traction control, and electronic stability control, the performance of these systems can be affected.

{ CAUTION:

If you add different sized wheels, your vehicle may not provide an acceptable level of performance and safety if tires not recommended for those wheels are selected. You may increase the chance that you will crash and suffer serious injury. Only use GM specific wheel and tire systems developed for your vehicle, and have them properly installed by a GM certified technician.

See Buying New Tires on page 5-86 and Accessories and Modifications on page 5-4 for additional information.

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Uniform Tire Quality Grading Quality grades can be found where applicable on the tire sidewall between tread shoulder and maximum section width. For example: Treadwear 200 Traction AA Temperature A The following information relates to the system developed by the United States National Highway Traffic Safety Administration (NHTSA), which grades tires by treadwear, traction, and temperature performance. This applies only to vehicles sold in the United States. The grades are molded on the sidewalls of most passenger car tires. The Uniform Tire Quality Grading (UTQG) system does not apply to deep tread, winter-type snow tires, space-saver, or temporary use spare tires, tires with nominal rim diameters of 10 to 12 inches (25 to 30 cm), or to some limited-production tires. While the tires available on General Motors passenger cars and light trucks may vary with respect to these grades, they must also conform to federal safety requirements and additional General Motors Tire Performance Criteria (TPC) standards.

Treadwear The treadwear grade is a comparative rating based on the wear rate of the tire when tested under controlled conditions on a specified government test course. For example, a tire graded 150 would wear one and a half (1.5) times as well on the government course as a tire graded 100. The relative performance of tires depends upon the actual conditions of their use, however, and may depart significantly from the norm due to variations in driving habits, service practices, and differences in road characteristics and climate. Traction – AA, A, B, C The traction grades, from highest to lowest, are AA, A, B, and C. Those grades represent the tire’s ability to stop on wet pavement as measured under controlled conditions on specified government test surfaces of asphalt and concrete. A tire marked C may have poor traction performance.

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Temperature – A, B, C The temperature grades are A (the highest), B, and C, representing the tire’s resistance to the generation of heat and its ability to dissipate heat when tested under controlled conditions on a specified indoor laboratory test wheel. Sustained high temperature can cause the material of the tire to degenerate and reduce tire life, and excessive temperature can lead to sudden tire failure. The grade C corresponds to a level of performance which all passenger car tires must meet under the Federal Motor Vehicle Safety Standard No. 109. Grades B and A represent higher levels of performance on the laboratory test wheel than the minimum required by law. It should be noted that the temperature grade for this tire is established for a tire that is properly inflated and not overloaded. Excessive speed, underinflation, or excessive loading, either separately or in combination, can cause heat buildup and possible tire failure.

Wheel Alignment and Tire Balance The tires and wheels on your vehicle were aligned and balanced carefully at the factory to give you the longest tire life and best overall performance. Adjustments to wheel alignment and tire balancing will not be necessary on a regular basis. However, if you notice unusual tire wear or your vehicle pulling to one side or the other, the alignment might need to be checked. If you notice your vehicle vibrating when driving on a smooth road, the tires and wheels might need to be rebalanced. See your dealer/retailer for proper diagnosis.

Wheel Replacement Replace any wheel that is bent, cracked, or badly rusted or corroded. If wheel nuts keep coming loose, the wheel, wheel bolts and wheel nuts should be replaced. If the wheel leaks air, replace it (except some aluminum wheels, which can sometimes be repaired). See your dealer/retailer if any of these conditions exist. Your dealer/retailer will know the kind of wheel you need.

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Each new wheel should have the same load-carrying capacity, diameter, width, offset and be mounted the same way as the one it replaces. If you need to replace any of the wheels, wheel bolts, wheel nuts or Tire Pressure Monitor System (TPMS) sensors, replace them only with new GM original equipment parts. This way, you will be sure to have the right wheel, wheel bolts, wheel nuts, and TPMS sensors for the vehicle.

{ CAUTION:

Using the wrong replacement wheels, wheel bolts, or wheel nuts on your vehicle can be dangerous. It could affect the braking and handling of your vehicle, make your tires lose air and make you lose control. You could have a collision in which you or others could be injured. Always use the correct wheel, wheel bolts, and wheel nuts for replacement.

Notice: The wrong wheel can also cause problems with bearing life, brake cooling, speedometer or odometer calibration, headlamp aim, bumper height, vehicle ground clearance, and tire or tire chain clearance to the body and chassis. Whenever a wheel, wheel bolt or wheel nut is replaced on a dual wheel setup, check the wheel nut torque after 100, 1,000 and 6,000 miles (160, 1 600 and 10 000 km) of driving. For proper torque, see “Wheel Nut Torque” under Capacities and Specifications on page 5-131. See Changing a Flat Tire on page 5-94 for more information. Used Replacement Wheels

{ CAUTION:

Putting a used wheel on the vehicle is dangerous. You cannot know how it has been used or how far it has been driven. It could fail suddenly and cause a crash. If you have to replace a wheel, use a new GM original equipment wheel.

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Tire Chains

{ CAUTION:

If your vehicle has dual wheels or P265/65R18, P275/55R20 or LT265/70R17 size tires, do not use tire chains. They can damage your vehicle because there is not enough clearance. Tire chains used on a vehicle without the proper amount of clearance can cause damage to the brakes, suspension, or other vehicle parts. The area damaged by the tire chains could cause you to lose control of your vehicle and you or others may be injured in a crash. Use another type of traction device only if its manufacturer recommends it for use on your vehicle and tire size combination and road conditions. Follow that manufacturer’s instructions.

CAUTION:

(Continued)

CAUTION:

(Continued)

To help avoid damage to your vehicle, drive slowly, readjust, or remove the device if it is contacting your vehicle, and do not spin your vehicle’s wheels. If you do find traction devices that will fit, install them on the rear tires.

If your vehicle does not have dual

Notice: wheels and has a tire size other than P265/65R18, P275/55R20 or LT265/70R17, use tire chains only where legal and only when you must. Use chains that are the proper size for your tires. Install them on the tires of the rear axle. Do not use chains on the tires of the front axle. Tighten them as tightly as possible with the ends securely fastened. Drive slowly and follow the chain manufacturer’s instructions. If you can hear the chains contacting your vehicle, stop and retighten them. If the contact continues, slow down until it stops. Driving too fast or spinning the wheels with chains on will damage your vehicle.

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If a Tire Goes Flat It is unusual for a tire to blowout while you are driving, especially if you maintain your vehicle’s tires properly. If air goes out of a tire, it is much more likely to leak out slowly. But if you should ever have a blowout, here are a few tips about what to expect and what to do: If a front tire fails, the flat tire creates a drag that pulls the vehicle toward that side. Take your foot off the accelerator pedal and grip the steering wheel firmly. Steer to maintain lane position, and then gently brake to a stop well out of the traffic lane. A rear blowout, particularly on a curve, acts much like a skid and may require the same correction you would use in a skid. In any rear blowout remove your foot from the accelerator pedal. Get the vehicle under control by steering the way you want the vehicle to go. It may be very bumpy and noisy, but you can still steer. Gently brake to a stop, well off the road if possible.

{ CAUTION:

Lifting a vehicle and getting under it to do maintenance or repairs is dangerous without the appropriate safety equipment and training. If a jack is provided with the vehicle, it is designed only for changing a flat tire. If it is used for anything else, you or others could be badly injured or killed if the vehicle slips off the jack. If a jack is provided with the vehicle, only use it for changing a flat tire.

If a tire goes flat, the next part shows how to use the jacking equipment to change a flat tire safely.

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Changing a Flat Tire If a tire goes flat, avoid further tire and wheel damage by driving slowly to a level place. Turn on the hazard warning flashers. See Hazard Warning Flashers on page 3-8.

{ CAUTION:

Changing a tire can be dangerous. The vehicle can slip off the jack and roll over or fall on you or other people. You and they could be badly injured or even killed. Find a level place to change your tire. To help prevent the vehicle from moving:

1. Set the parking brake firmly. 2. Put the shift lever in P (Park). 3. If you have a four-wheel-drive vehicle, be sure the transfer case is in a drive gear — not in N (Neutral).

4. Turn off the engine and do not restart while

the vehicle is raised.

CAUTION:

(Continued)

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CAUTION:

(Continued)

5. Do not allow passengers to remain in the

vehicle.

6. Put the wheel blocks at the front and rear

of the tire farthest away from the one being changed. That would be the tire on the other side, at the opposite end of the vehicle.

When the vehicle has a flat tire (B), use the following example as a guide to assist you in the placement of wheel blocks (A).

A. Wheel Block B. Flat Tire The following information explains how to use the jack and change a tire.

Removing the Spare Tire and Tools

Crew Cab

A. Wing Nut Retaining

Tool Kit B. Tool Kit C. Wheel Blocks

D. Jack E. Jack Knob F. Wing Nut Retaining

Wheel Blocks

Regular Cab

A. Wing Nut Retaining

Tool Kit B. Tool Kit C. Wheel Blocks

D. Jack E. Jack Knob F. Wing Nut Retaining

Wheel Blocks

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For regular cab models, the equipment you will need is behind the passenger’s seat. For extended and crew cab models, the equipment is on the shelf behind the passenger’s side second row seat. 1. Turn the knob on the jack counterclockwise to lower

the jack head to release the jack from its holder.

2. Remove the wheel blocks and the wheel block

retainer by turning the wing nut counterclockwise. 3. Remove the wing nut used to retain the storage

bag and tools by turning it counterclockwise.

You will use the jack handle extensions and the wheel wrench to remove the underbody-mounted spare tire.

Extended Cab

A. Wing Nut

Retaining Tool Kit

B. Tool Kit

C. Wheel Blocks D. Jack E. Jack Knob

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1. Open the spare tire lock cover on the bumper and use the ignition key to remove the spare tire lock (J). To remove the spare tire lock, insert the ignition key turn and pull straight out.

2. Assemble the wheel wrench (H) and the two jack

handle extensions (I) as shown.

A. Spare Tire (Valve

G. Hoist Shaft

Stem Pointed Down)

Access Hole

B. Hoist Assembly C. Hoist Cable D. Tire/Wheel Retainer E. Hoist Shaft F. Hoist End of

Extension Tool

H. Wheel Wrench I. Jack Handle

Extensions

J. Spare Tire Lock

(If equipped)

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3. Insert the hoist end (open end) (F) of the extension through the hole (G) in the rear bumper. Do not use the chiseled end of the wheel wrench.

4. Turn the wheel wrench (H) counterclockwise to lower the spare tire to the ground. Continue to turn the wheel wrench until the spare tire can be pulled out from under the vehicle. If the spare tire does not lower to the ground, the secondary latch is engaged causing the tire not to lower. See Secondary Latch System on page 5-107.

Be sure the hoist end of the extension (F) connects to the hoist shaft (E). The ribbed square end of the extension is used to lower the spare tire.

5. Use the wheel wrench hook which allows you to pull the hoist cable towards you to assist in reaching the spare tire.

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Once the retainer is separated from the guide pin, tilt the retainer and pull it through the center of the wheel along with the cable and guide latch.

7. Put the spare tire near the flat tire.

6. Tilt the tire toward the vehicle with some slack

in the cable to access the tire/wheel retainer. Separate the retainer from the guide pin by sliding the retainer up the pin while pressing down on the latch.

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Removing the Flat Tire and Installing the Spare Tire Use the following pictures and instructions to remove the flat tire and raise the vehicle.

2. If your vehicle has

wheel nut caps, loosen them by turning the wheel wrench counterclockwise.

If the vehicle has a center cap with wheel nut caps, the wheel nut caps are designed to stay with the center cap after they are loosened. Remove the entire center cap.

The tools you will be using include the jack (A), the wheel blocks (B), the jack handle (C), the jack handle extensions (D), and the wheel wrench (E). 1. Do a safety check before proceeding. See Changing

a Flat Tire on page 5-94 for more information.

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If the wheel has a smooth center cap, place the chisel end of the wheel wrench in the slot on the wheel, and gently pry it out.

3. Use the wheel wrench and turn it counterclockwise to loosen the wheel nuts. Do not remove the wheel nuts yet.

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Front Position - 1500

Models

Front Position - All

Other Models

Rear Position – 1500

Models

Rear Position – All

Other Models

4. Position the jack under the vehicle as shown. If the

flat tire is on the front of the vehicle (1500 Model vehicles), position the jack under the bracket attached to the vehicle’s frame, behind the flat tire. If the flat tire is on the front of the vehicle (all other models), position the jack on the frame behind the flat tire.

If the flat tire is on the rear, for 1500 models position the jack under the rear axle about 2 inches (5 cm) inboard of the shock absorber bracket; for all other models, position the jack under the rear axle between the spring anchor and the shock absorber bracket. If you have added a snow plow to the front of your vehicle, lower the snow plow fully before raising the vehicle. Make sure that the jack head is positioned so that the rear axle is resting securely between the grooves that are on the jack head.

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5. Turn the wheel wrench clockwise to raise the

vehicle. Raise the vehicle far enough off the ground so there is enough room for the spare tire to fit under the wheel well.

6. Remove all the wheel nuts and take off the flat tire.

{ CAUTION:

Getting under a vehicle when it is jacked up is dangerous. If the vehicle slips off the jack, you could be badly injured or killed. Never get under a vehicle when it is supported only by a jack.

{ CAUTION:

Raising your vehicle with the jack improperly positioned can damage the vehicle and even make the vehicle fall. To help avoid personal injury and vehicle damage, be sure to fit the jack lift head into the proper location before raising the vehicle.

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{ CAUTION:

Rust or dirt on a wheel, or on the parts to which it is fastened, can make wheel nuts become loose after time. The wheel could come off and cause an accident. When changing a wheel, remove any rust or dirt from places where the wheel attaches to the vehicle. In an emergency, use a cloth or a paper towel to do this; but be sure to use a scraper or wire brush later, if needed, to get all the rust or dirt off. See Changing a Flat Tire on page 5-94.

8. Install the spare tire.

7. Remove any rust or dirt

from the wheel bolts, mounting surfaces, and spare wheel.

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{ CAUTION:

{ CAUTION:

Never use oil or grease on bolts or nuts because the nuts might come loose. The vehicle’s wheel could fall off, causing a crash.

9. Put the wheel nuts back on with the rounded end of

the nuts toward the wheel.

10. Tighten each wheel nut by hand. Then use the wheel wrench to tighten the nuts until the wheel is held against the hub.

11. Turn the wheel wrench counterclockwise to lower

the vehicle. Lower the jack completely.

If wheel studs are damaged, they can break. If all the studs on a wheel broke, the wheel could come off and cause a crash. If any stud is damaged because of a loose-running wheel, it could be that all of the studs are damaged. To be sure, replace all studs on the wheel. If the stud holes in a wheel have become larger, the wheel could collapse in operation. Replace any wheel if its stud holes have become larger or distorted in any way. Inspect hubs and hub-piloted wheels for damage. Because of loose running wheels, piloting pad damage may occur and require replacement of the entire hub, for proper centering of the wheels. When replacing studs, hubs, wheel nuts or wheels, be sure to use GM original equipment parts.

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{ CAUTION:

Wheel nuts that are improperly or incorrectly tightened can cause the wheels to become loose or come off. The wheel nuts should be tightened with a torque wrench to the proper torque specification after replacing. Follow the torque specification supplied by the aftermarket manufacturer when using accessory locking wheel nuts. See Capacities and Specifications on page 5-131 for original equipment wheel nut torque specifications.

Improperly tightened wheel nuts can

Notice: lead to brake pulsation and rotor damage. To avoid expensive brake repairs, evenly tighten the wheel nuts in the proper sequence and to the proper torque specification. See Capacities and Specifications on page 5-131 for the wheel nut torque specification.

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12. Tighten the nuts firmly in a crisscross sequence as

shown by turning the wheel wrench clockwise. Have a technician check the wheel nut tightness of all wheels with a torque wrench after the first 100 miles (160 km) and then 1,000 miles (1600 km) after that. Repeat this service whenever you have a tire removed or serviced. See Capacities and Specifications on page 5-131 for more information. When you reinstall the regular wheel and tire, you must also reinstall either the center cap, or bolt-on hub cap, depending on what your vehicle is equipped with. For center caps, place the cap on the wheel and tap it into place until it seats flush with the wheel. The cap only goes on one way. Be sure to line up the tab on the center cap with the indentation on the wheel. For bolt-on hub caps, align the plastic nut caps with the wheel nuts and then tighten by hand. Then use the wheel wrench to tighten.

Secondary Latch System Your vehicle has an underbody-mounted tire hoist assembly equipped with a secondary latch system. It is designed to stop the spare tire from suddenly falling off your vehicle. For the secondary latch to work, the spare must be installed with the valve stem pointing down. See Storing a Flat or Spare Tire and Tools on page 5-110.

{ CAUTION:

Before beginning this procedure read all the instructions. Failure to read and follow the instructions could damage the hoist assembly and you and others could get hurt. Read and follow the instructions listed next.

To release the spare tire from the secondary latch:

1. Check under the

vehicle to see if the cable end is visible. If the cable is not visible proceed to Step 6.

2. If it is visible, first try to tighten the cable by turning the wheel wrench clockwise until you hear two clicks or feel it skip twice. You cannot overtighten the cable.

3. Loosen the cable by turning the wrench

counterclockwise three or four turns.

4. Repeat this procedure at least two times. If the

spare tire lowers to the ground, continue with Step 5 of Removing the Spare Tire and Tools on page 5-95.

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5. If the spare does not lower, turn the wrench

counterclockwise until approximately 6 inches (15 cm) of cable is exposed.

6. Stand the wheel blocks on their shortest ends, with

the backs facing each other.

7. Place the bottom

edge of the jack (A) on the wheel blocks (B), separating them so that the jack is balanced securely.

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8. Attach the jack handle, extension, and wheel

wrench to the jack and place it (with the wheel blocks) under the vehicle toward the front of the rear bumper.