2007 Cadillac DTS Owners Manual

in the mixture can freeze and crack the engine, radiator, heater core, and other parts. If you have to add coolant more than two times a year, have your dealer check your cooling system. Notice: If you use extra inhibitors and/or additives in your vehicle’s cooling system, you could damage your vehicle. Use only the proper mixture of the engine coolant listed in this manual for the cooling system. See Recommended Fluids and Lubricants on page 467 for more information.

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Checking Coolant

The engine coolant surge tank is located toward the rear of the engine compartment on the passenger’s side of the vehicle.

For more information on location, see Engine Compartment Overview on page 356.

{CAUTION:

Turning the surge tank pressure cap when the engine and radiator are hot can allow steam and scalding liquids to blow out and burn you badly. Never turn the surge tank pressure cap — even a little — when the engine and radiator are hot.

The vehicle must be on a level surface. When your engine is cold, the coolant level should be at the FULL COLD mark, located on the side of the surge tank that faces the engine.

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Adding Coolant If you need more coolant, add the proper DEX-COOL® coolant mixture at the coolant surge tank, but only when the engine is cool.

{CAUTION:

You can be burned if you spill coolant on hot engine parts. Coolant contains ethylene glycol, and it will burn if the engine parts are hot enough. Do not spill coolant on a hot engine.

When replacing the pressure cap, make sure to turn the cap until it clicks.

If the pressure cap is not tightly

Coolant Surge Tank Pressure Cap Notice: installed, coolant loss and possible engine damage may occur. Be sure the cap is properly and tightly secured. See Engine Compartment Overview on page 356
for more information on location.

Engine Overheating You will find an ENGINE OVERHEATED IDLE ENGINE message or an ENGINE OVERHEATED STOP ENGINE message displayed in the Driver Information Center (DIC). See DIC Warnings and Messages on page 239 for more information. You will also hear a chime. There is also an engine temperature warning light and/or gage on the instrument panel cluster. See Engine Coolant Temperature Warning Light on page 226 and Engine Coolant Temperature Gage on page 226.

369

If Steam Is Coming From Your Engine

{CAUTION:

Steam from an overheated engine can burn you badly, even if you just open the hood. Stay away from the engine if you see or hear steam coming from it. Turn it off and get everyone away from the vehicle until it cools down. Wait until there is no sign of steam or coolant before you open the hood. If you keep driving when the vehicles engine is overheated, the liquids in it can catch fire. You or others could be badly burned. Stop your engine if it overheats, and get out of the vehicle until the engine is cool. See Overheated Engine Protection Operating Mode on page 371 for information on driving to a safe place in an emergency.

370

If your engine catches fire because

Notice: you keep driving with no coolant, your vehicle can be badly damaged. The costly repairs would not be covered by your warranty. See Overheated Engine Protection Operating Mode on page 371 for information on driving to a safe place in an emergency.

If No Steam Is Coming From Your Engine An overheat warning, along with a low coolant message, can indicate a serious problem. If you get an engine overheat warning with no low coolant message, but see or hear no steam, the problem may not be too serious. Sometimes the engine can get a little too hot when you: (cid:127) Climb a long hill on a hot day. (cid:127) Stop after high-speed driving. (cid:127) Idle for long periods in traffic. (cid:127) Tow a trailer.

If you get the overheat warning with no sign of steam, try this for a minute or so: 1. In heavy traffic, let the engine idle in

NEUTRAL (N) while stopped. If it safe to do so, pull off the road, shift to PARK (P) or NEUTRAL (N) and let the engine idle.

2. Set the climate controls to the highest

heat setting and fan speed and open the windows as necessary.

If you no longer have the overheat warning, you can drive. Just to be safe, drive slower for about 10 minutes. If the warning does not come back on, you can drive normally. If the warning continues, pull over, stop, and park your vehicle right away. If there is still no sign of steam, idle the engine for three minutes while you are parked. If you still have the warning, turn off the engine and get everyone out of the vehicle until it cools down. Also, see “Overheated Engine Protection Operating Mode” later in this section. You may decide not to lift the hood but to get service help right away.

Overheated Engine Protection Operating Mode If an overheated engine condition exists and the message ENGINE OVERHEATED STOP ENGINE is displayed, an overheat protection mode which alternates firing groups of cylinders helps prevent engine damage. In this mode, you will notice a loss in power and engine performance. This operating mode allows your vehicle to be driven to a safe place in an emergency. Driving extended miles (km) and/or towing a trailer in the overheat protection mode should be avoided. Notice: After driving in the overheated engine protection operating mode, to avoid engine damage, allow the engine to cool before attempting any repair. The engine oil will be severely degraded. Repair the cause of coolant loss, change the oil and reset the oil life system. See Engine Oil on page 357.

371

Cooling System When you decide it is safe to lift the hood, here is what you will see:

4.6L L37 Engine shown, 4.6L LD8 Engine similar

A. Coolant Surge Tank with Pressure Cap

B. Electric Engine Cooling Fans

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1

{CAUTION:

An electric engine cooling fan under the hood 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.

If the coolant inside the coolant surge tank is boiling, do not do anything else until it cools down. The vehicle should be parked on a level surface.

{CAUTION:

Heater and radiator hoses, and other engine parts, can be very hot. Do not touch them. If you do, you can be burned. Do not run the engine if there is a leak. If you run the engine, it could lose all coolant. That could cause an engine fire, and you could be burned. Get any leak fixed before you drive the vehicle.

If there seems to be no leak, with the engine on, check to see if the electric engine cooling fans are running. If the engine is overheating, both fans should be running. If they are not, your vehicle needs service. Notice: Engine damage from running your engine without coolant is not covered by your warranty. See Overheated Engine Protection Operating Mode on page 371 for information on driving to a safe place in an emergency. Notice: Using coolant other than DEX-COOL® may cause premature engine, heater core, or radiator corrosion. In addition, the engine coolant could require changing sooner, at 30,000 miles (50 000 km) or 24 months, whichever occurs first. Any repairs would not be covered by your warranty. Always use DEX-COOL® (silicate-free) coolant in your vehicle.

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How to Add Coolant to the Coolant Surge Tank If you have not found a problem yet, check to see if coolant is visible in the surge tank. If coolant is visible but the level is not at the FULL COLD mark located on the side of the surge tank, add enough of a 50/50 mixture of clean, drinkable water and DEX-COOL® coolant at the coolant surge tank to bring the level to the FULL COLD mark, but be sure the cooling system, including the coolant surge tank pressure cap, is cool before you do it. See Engine Coolant on page 366
for more information.

If no coolant is visible in the surge tank, add coolant as follows:

{CAUTION:

Steam and scalding liquids from a hot cooling system can blow out and burn you badly. They are under pressure, and if you turn the coolant surge tank pressure cap — even a little — they can come out at high speed. Never turn the cap when the cooling system, including the coolant surge tank pressure cap, is hot. Wait for the cooling system and coolant surge tank pressure cap to cool if you ever have to turn the pressure cap.

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{CAUTION:

{CAUTION:

Adding only plain water to your cooling system can be dangerous. Plain water, or some other liquid such as alcohol, can boil before the proper coolant mixture will. Your vehicle’s coolant warning system is set for the proper coolant mixture. With plain water or the wrong mixture, your engine could get too hot but you would not get the overheat warning. Your engine could catch fire and you or others could be burned. Use a 50/50 mixture of clean, drinkable water and DEX-COOL® coolant.

In cold weather, water can freeze and

Notice: crack the engine, radiator, heater core and other parts. Use the recommended coolant and the proper coolant mixture.

You can be burned if you spill coolant on hot engine parts. Coolant contains ethylene glycol and it will burn if the engine parts are hot enough. Do not spill coolant on a hot engine.

1. You can remove the coolant surge tank pressure cap when the cooling system, including the coolant surge tank pressure cap and upper radiator hose, is no longer hot.

Turn the pressure cap slowly counterclockwise. If you hear a hiss, wait for that to stop. A hiss means there is still some pressure left.

2. Then keep turning the cap and remove it.

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3. Fill the coolant

surge tank with the proper mixture to the FULL COLD mark on the side of the coolant surge tank.

4. With the coolant surge tank cap off, start the

engine and let it run until you can feel the upper radiator hose getting hot. Watch out for the engine cooling fans. By this time, the coolant level inside the coolant surge tank may be lower. If the level is lower, add more of the proper mixture to the coolant surge tank until the level reaches the FULL COLD mark on the side of the coolant surge tank.

5. Then replace the cap. Be sure the cap is

hand-tight and fully seated.

4.6L L37 Engine shown, 4.6L LD8 Engine similar

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Power Steering Fluid

The power steering fluid reservoir is located next to the underhood fuse block on the passenger’s side of the vehicle. See Engine Compartment Overview on page 356 for more information on location.

When to Check Power Steering Fluid It is not necessary to regularly check power steering fluid unless you suspect there is a leak in the system or you hear an unusual noise. A fluid loss in this system could indicate a problem. Have the system inspected and repaired.

How to Check Power Steering Fluid To check the power steering fluid, do the following: 1. Turn the key off and let the engine

compartment cool down.

2. Wipe the cap and the top of the reservoir clean. 3. Unscrew the cap and wipe the dipstick with a

clean rag.

4. Replace the cap and completely tighten it. 5. Remove the cap again and look at the

fluid level on the dipstick.

The level should be at the FULL COLD mark. If necessary, add only enough fluid to bring the level up to the mark. What to Use To determine what kind of fluid to use, see Recommended Fluids and Lubricants on page 467. Always use the proper fluid. Failure to use the proper fluid can cause leaks and damage hoses and seals.

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Notice: (cid:127) When using concentrated washer fluid, follow the manufacturer’s instructions for adding water.

(cid:127) Do not mix water with ready-to-use washer

fluid. Water can cause the solution to freeze and damage your washer fluid tank and other parts of the washer system. Also, water does not clean as well as washer fluid.

(cid:127) Fill your washer fluid tank only

three-quarters full when it is very cold. This allows for expansion if freezing occurs, which could damage the tank if it is completely full.

(cid:127) Do not use engine coolant (antifreeze) in

your windshield washer. It can damage your washer system and paint.

Windshield Washer Fluid What to Use When you need windshield washer fluid, be sure to read the manufacturer’s instructions before use. If you will be operating your vehicle in an area where the temperature may fall below freezing, use a fluid that has sufficient protection against freezing. Adding Washer Fluid The WASHER FLUID LOW ADD FLUID message will be displayed on the Driver Information Center (DIC) when the fluid is low. See DIC Warnings and Messages on page 239 for more information.

Open the cap with the washer symbol on it. Add washer fluid until the tank is full. See Engine Compartment Overview on page 356
for reservoir location.

378

Brakes Brake Fluid

Your brake master cylinder reservoir is filled with DOT-3 brake fluid. See Engine Compartment Overview on page 356 for reservoir location and access.

There are only two reasons why the brake fluid level in the reservoir might go down. The first is that the brake fluid goes down to an acceptable level during normal brake lining wear. When new linings are put in, the fluid level goes back up. The other reason is that fluid is leaking out of the brake system. If it is, you should have your brake system fixed, since a leak means that sooner or later your brakes will not work well, or will not work at all.

So, it is not a good idea to top off your brake fluid. Adding brake fluid will not correct a leak. If you add fluid when your linings are worn, then you will have too much fluid when you get new brake linings. You should add or remove brake fluid, as necessary, only when work is done on the brake hydraulic system.

{CAUTION:

If your vehicle has too much brake fluid, it can spill on the engine. The fluid will burn if the engine is hot enough. You or others could be burned, and your vehicle could be damaged. Add brake fluid only when work is done on the brake hydraulic system.

If the ignition is on and the brake fluid is low, the SERVICE BRAKE SYSTEM message will be displayed in the Driver Information Center (DIC). See DIC Warnings and Messages on page 239.

379

What to Add When you do need brake fluid, use only DOT-3
brake fluid. Use new brake fluid from a sealed container only. See Recommended Fluids and Lubricants on page 467. Always clean the brake fluid reservoir cap and the area around the cap before removing it. This will help keep dirt from entering the reservoir.

{CAUTION:

With the wrong kind of fluid in the brake system, the brakes may not work well, or they may not even work at all. This could cause a crash. Always use the proper brake fluid.

Notice: (cid:127) Using the wrong fluid can badly damage brake system parts. For example, just a few drops of mineral-based oil, such as engine oil, in the brake system can damage brake system parts so badly that they will have to be replaced. Do not let someone put in the wrong kind of fluid. If you spill brake fluid on your vehicle’s painted surfaces, the paint finish can be damaged. Be careful not to spill brake fluid on your vehicle. If you do, wash it off immediately. See Washing Your Vehicle on page 435.

(cid:127)

Brake Wear Your vehicle has four-wheel disc brakes. Disc brake pads have built-in wear indicators that make a high-pitched warning sound when the brake pads are worn and new pads are needed. The sound may come and go or be heard all the time your vehicle is moving, except when you are pushing on the brake pedal firmly.

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{CAUTION:

The brake wear warning sound means that soon the brakes will not work well. That could lead to an accident. When you hear the brake wear warning sound, have your vehicle serviced.

Notice: Continuing to drive with worn-out brake pads could result in costly brake repair. Some driving conditions or climates may cause a brake squeal when the brakes are first applied or lightly applied. This does not mean something is wrong with your brakes. Properly torqued wheel nuts are necessary to help prevent brake pulsation. When tires are rotated, inspect brake pads for wear and evenly tighten wheel nuts in the proper sequence to GM torque specifications. Brake linings should always be replaced as complete axle sets.

Brake Pedal Travel See your dealer if the brake pedal does not return to normal height, or if there is a rapid increase in pedal travel. This could be a sign of brake trouble. Brake Adjustment Every time you apply the brakes, with or without the vehicle moving, your brakes adjust for wear. Replacing Brake System Parts The braking system on a vehicle is complex. Its many parts have to be of top quality and work well together if the vehicle is to have really good braking. Your vehicle was designed and tested with top-quality GM brake parts. When you replace parts of your braking system — for example, when your brake linings wear down and you need new ones put in — be sure you get new approved replacement parts. If you do not, your brakes may no longer work properly. For example, if someone puts in brake linings that are wrong for your vehicle, the balance between your front and rear brakes can change — for the worse. The braking performance you have come to expect can change in many other ways if someone puts in the wrong replacement brake parts.

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Battery Your vehicle has a maintenance free battery. When it is time for a new battery, get one that has the replacement number shown on the original battery’s label. We recommend an ACDelco® replacement battery. Warning: Battery posts, terminals, and related accessories contain lead and lead compounds, chemicals known to the State of California to cause cancer and reproductive harm. Wash hands after handling. The battery is located under the rear seat cushion. To access the battery, see Rear Underseat Fuse Block on page 447. You do not need to access the battery to jump start your vehicle. See Jump Starting on page 384.

{CAUTION:

A battery that is not properly vented can let sulfuric acid fumes into the area under the rear seat cushion. These fumes can damage your rear seat safety belt systems. You may not be able to see this damage, and the safety belts might not provide the protection needed in a crash. If a replacement battery is ever needed, it must be vented in the same manner as the original battery. Always make sure that the vent hose is properly reattached before reinstalling the seat cushion.

382

Vehicle Storage If you are not going to drive your vehicle for 25 days or more, remove the black, negative (−) cable from the battery. This will help keep your battery from running down.

{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 384 for tips on working around a battery without getting hurt.

383

To be sure the vent hose (A) is properly attached, the vent hose connectors (B) must be securely reattached to the vent outlets (C) on each side of the battery, and the vent assembly grommet (D) must be secured to the floor pan (E).

Jump Starting If your vehicle’s battery 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:127) They contain acid that can burn you. (cid:127) They contain gas that can explode

(cid:127) They contain enough electricity to

or ignite.

burn you.

If you do not follow these steps exactly, some or all of these things can hurt you.

384

Ignoring these steps could result in

Notice: costly damage to your vehicle that would not be covered by your warranty. Trying to start your vehicle by pushing or pulling it will not work, and it could damage your 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

Notice: a 12-volt 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. 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 a ground connection you do not want. 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 an automatic transaxle in PARK (P) or a manual transaxle in NEUTRAL before setting the parking brake.

Notice: If you leave your radio or other accessories on during the jump starting procedure, they could be damaged. The repairs would not be covered by your warranty. Always turn off your radio and other accessories when jump starting your vehicle. 3. 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 lamps that are not needed. This will avoid sparks and help save both batteries. And it could save the radio!

4. Open the hoods and locate the positive (+) and negative (−) terminal locations on the other vehicle. Your vehicle has a remote positive (+) jump starting terminal and a remote negative (−) jump starting terminal.

4.6L LD8 Engine shown,

4.6L L37 Engine

similar

The remote positive (+) terminal is located in the engine compartment on the passenger’s side of the vehicle. Lift the red plastic cap to access the terminal. See Engine Compartment Overview on page 356 for more information on the location of the remote positive (+) terminal. A second remote positive (+) terminal is located on the rear underseat fuse block.

385

The remote negative (−) terminal is located behind the power steering pulley, near the engine cover. It is marked GND (−). You will not see the battery of your vehicle under the hood. It is located under the rear passenger’s seat. You will not need to access the battery for jump starting. The remote terminals are for that purpose.

{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.

386

{CAUTION:

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

5. 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.

6. Connect the red positive (+) cable to the

remote positive (+) terminal location on the vehicle with the dead battery. Use a remote positive (+) terminal if the vehicle has one.

7. Do not let the other end touch metal. Connect

it to the positive (+) terminal location of the vehicle with the good battery. Use a remote positive (+) terminal if the vehicle has one. 8. Now connect the black negative (−) cable to the negative (−) terminal location of the vehicle with the good battery. Use a remote negative (−) terminal if the vehicle has one. Do not let the other end of the cable touch anything until the next step. The other end of the negative (−) cable does not go to the dead battery. It goes to a heavy, unpainted metal engine part or to a remote negative (−) terminal on the vehicle with the dead battery.

387

9. Connect the other end of the negative (−) cable to the negative (−) terminal location on the vehicle with the dead battery. Your vehicle has a remote negative (−) terminal marked GND (−).

10. Now start the vehicle with the good battery

and run the engine for a while.

11. Try to start the vehicle that had the dead battery. If it will not start after a few tries, it probably needs service.

If the jumper cables are connected

Notice: or removed in the wrong order, electrical shorting may occur and damage the vehicle. The repairs would not be covered by your 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.

388

Jumper Cable Removal

A. Heavy, Unpainted Metal Engine Part or

Remote Negative (−) Terminal (GND)

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 dead 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 remote positive (+) terminal cover

to its original position.

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

Notice: To make sure your headlamps are aimed properly, read all the instructions before beginning. Failure to follow these instructions could cause damage to headlamp parts. The vehicle should be properly prepared as follows: (cid:127) The vehicle should be placed so the headlamps

are 25 ft. (7.6 m) from a light colored wall.

(cid:127) The vehicle must have all four tires on a level surface which is level all the way to the wall.

(cid:127) The vehicle should be placed so it is

perpendicular to the wall.

(cid:127) The vehicle should not have any snow, ice, or

mud on it.

(cid:127) The vehicle should be fully assembled and all other work stopped while headlamp aiming is being performed.

(cid:127) The vehicle should be normally loaded with a

full tank of fuel and one person or 160 lbs (75 kg) sitting on the driver’s seat. (cid:127) Tires should be properly inflated. (cid:127) The spare tire is in its original location in

the vehicle.

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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. To adjust the vertical aim, do the following: 1. Open the hood. See Hood Release on

page 355 for more information.

2. Find the center line running through the lens

of the headlamp.

3. Measure the distance from the ground to the

center line running through the lens of the headlamp. Record the distance.

390

4. At the wall measure from the ground upward (A) to the recorded distance from Step 3 and mark it.

5. Draw or tape a horizontal line the width of

the vehicle at the wall where it was marked 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 aimed. This should allow only the beam of light from the headlamp being aimed to be seen on the flat surface.

7. Locate the vertical headlamp aiming screws. They are located under the hood near each headlamp assembly. First lift the flap to access either of them. Each one is the top outboard screw by the “ V” on the cover panel next to the aiming flap. The adjustment screw can be turned with a 6 mm hex wrench.

8. Turn the vertical aiming screw until the

headlamp beam is aimed to the horizontal tape line. If you turn it clockwise, it will raise the beam and if you turn it counterclockwise, it will lower the beam. The top edge of the cut-off should be positioned at the bottom edge of the horizontal tape line.

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.

391

Bulb Replacement It is recommended that all bulbs be replaced by your dealer.

High Intensity Discharge (HID) Lighting

{CAUTION:

The low beam high intensity discharge lighting system operates at a very high voltage. If you try to service any of the system components, you could be seriously injured. Have your dealer or a qualified technician service them.

Your vehicle has HID headlamps. After your vehicle’s HID headlamp bulb has been replaced, you may notice that the beam is a slightly different shade than it was originally. This is normal.

392

Windshield Wiper Blade Replacement Windshield wiper blades should be inspected for wear or cracking. See Scheduled Maintenance on page 457 for more information on wiper blade inspection. Replacement blades come in different types and are removed in different ways. Here’s how to remove the wiper blade: 1. Turn the engine off. 2. Lift the windshield wiper arm and blade away

from the windshield.

3. Pull the clip up from the blade connecting point,

and pull the blade assembly down toward the windshield to remove it from the wiper arm.

4. Install the new wiper blade onto the wiper arm

and firmly press down on the clip to snap it into place.

To remove and replace the wiper blade element do the following: 1. The wiper blade element has two notches at

one end which are engaged by the bottom claw set of the wiper blade. At the notched end of the wiper blade, pull the wiper blade element from the wiper blade assembly.

2. To replace the element, start at the heel end of the wiper blade, which is the end nearest to the base of the wiper arm, and slide the wiper blade element, notched end last, into the wiper blade claw sets.

3. To engage the last claw into the notched end

of the wiper blade element, squeeze the wiper blade element at the notched area, and push the wiper blade element so the claw fits into the notch.

4. Be sure the two wiper blade element notches are engaged by the last claw set, and that all the other claws are properly engaged in the slots of the wiper blade element on both sides.

A. Correct Installation B. Incorrect Installation For the proper type and size windshield wiper blades, see Normal Maintenance Replacement Parts on page 468.

393

CAUTION:

(Continued)

Tire pressure should be checked when your tires are cold. See Inflation - Tire Pressure on page 402.

(cid:127) 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:127) Worn, old tires can cause accidents.

If your tread is badly worn, or if your tires have been damaged, replace them.

See High-Speed Operation on page 405
for inflation pressure adjustment for high speed driving.

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 GM Warranty booklet for details. For additional information refer to the tire manufacturer’s booklet included with your vehicle.

{CAUTION:

(cid:127) Poorly maintained and improperly

used tires are dangerous.

(cid:127) Overloading your tires can cause

overheating as a result of too much friction. You could have an air-out and a serious accident. See Loading Your Vehicle on page 327.

(cid:127) 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.

CAUTION:

(Continued)

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Tire Sidewall Labeling Useful information about a tire is molded into its sidewall.

Passenger Car Tire Example

(A) Tire Size: The tire size 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 the 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.

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(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 414.

(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 402
and Loading Your Vehicle on page 327.

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Compact Spare Tire Example

(A) Temporary Use Only: The compact spare tire or temporary use tire has a tread life of approximately 3,000 miles (5 000 km) and should not be driven at speeds over 65 mph (105 km/h). The compact spare tire is for emergency use when a regular road tire has lost air and gone flat. See Spare Tire on page 430 and If a Tire Goes Flat on page 419.

(B) Tire Ply Material: The type of cord and number of plies in the sidewall and under the tread.

(C) Tire Identification Number (TIN): 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.

(D) Maximum Cold Inflation Load Limit: Maximum load that can be carried and the maximum pressure needed to support that load. See Inflation - Tire Pressure on page 402 and Loading Your Vehicle on page 327.

(E) Tire Inflation: The temporary use tire or compact spare tire should be inflated to 60 psi (420 kPa). For more information on tire pressure and inflation see Inflation - Tire Pressure on page 402 and Spare Tire on page 430.

(F) Tire Size: A combination of letters and numbers define a tire’s width, height, aspect ratio, construction type and service description. The letter T as the first character in the tire size means the tire is for temporary use only.

(G) 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.

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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.

(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 Tire Example

(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 402. Tire Size The following illustration shows an example of a tire size.

(A) 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 60, as shown in item C of the illustration, it would mean that the tire’s sidewall is 60 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 range and speed rating of the tire. The load index represents the load carry capacity a tire is certified to carry. The load index can range from 1 to 279. The speed rating is the maximum speed a tire is certified to carry a load. Speed ratings range from A to Z.

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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/ transaxle, 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 402.

Curb Weight: This means 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 Your Vehicle on page 327.

GAWR FRT: Gross Axle Weight Rating for the front axle. See Loading Your Vehicle on page 327.

GAWR RR: Gross Axle Weight Rating for the rear axle. See Loading Your Vehicle on page 327.

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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 may 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 Your Vehicle on page 327.

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 402 and Loading Your Vehicle on page 327.

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.

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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 411.

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 414.

Vehicle Capacity Weight: The number of designated seating positions multiplied by 150 lbs (68 kg) plus the rated cargo load. See Loading Your Vehicle on page 327.

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 Your Vehicle on page 327.

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:127) Too much flexing (cid:127) Too much heat

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(cid:127) Tire overloading (cid:127) Premature or irregular wear (cid:127) Poor handling (cid:127) Reduced fuel economy If your tires have too much air (over-inflation), you can get the following: (cid:127) Unusual wear (cid:127) Poor handling (cid:127) Rough ride (cid:127) Needless damage from road hazards A Tire and Loading Information label is attached to the vehicle’s center pillar. This label lists your vehicle’s original equipment tires and shows 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 Your Vehicle on page 327. How you load your vehicle affects the 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 spare tire. If your vehicle has a compact spare tire, it should be at 60 psi (420 kPa). For additional information see Spare Tire on page 430. 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 are under-inflated. 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).

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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 inflation 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. Re-check 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. Your vehicle has a Tire Pressure Monitor System (TPMS) that sends tire pressure information to the Driver Information Center (DIC). Using the DIC control buttons, the driver is able to check tire pressure levels in all four road tires. See Tire Pressure Monitor System on page 406 and DIC Controls and Displays on page 233 for additional information.

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(cid:127)

Professional Vehicle The proper inflation of the tires on your professional vehicle depends on the type of tires on it. (cid:127)

If your vehicle has P235/60R17 size tires, the cold inflation pressure is 41 psi (284 kPa). If your vehicle has LT235/60R17E size tires, the cold inflation pressure depends on the vehicle mass and should be determined by the vehicle coach-builder. A tire and loading information label provided by the final stage manufacturer should be attached to the B-pillar on the driver’s side of the vehicle. If the final stage manufacturer’s label is not present, the coach-builder should be consulted. Do not use the tire pressures indicated on the General Motors label. These tire pressures are for the incomplete vehicle and are not the correct tire pressures for the completed professional vehicle.

Operation at inflation pressures below this recommendation may cause your tires to become overloaded.

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.

If your vehicle has P235/55R17 or P245/50R18
size tires, and you will be driving at speeds of 100 mph (160 km/h) or higher, where it is legal, set the cold inflation pressure to the maximum inflation pressure shown on the tire sidewall, or 38 psi (265 kPa), whichever is lower. See the example following. Example: You will find the maximum load and inflation pressure molded on the tire’s sidewall, in small letters, near the rim flange. It will read something like this: Maximum load 690 kg (1521 lbs) 300 kPa (44 psi) Max. Press. For this example, you would set the inflation pressure for high-speed driving at 38 psi (265 kPa). 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 Your Vehicle on page 327.

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Tire Pressure Monitor System The Tire Pressure Monitor System (TPMS) uses radio and sensor technology to check tire pressure levels. Sensors are mounted on each tire and wheel assembly, except the spare tire. The TPMS sensors monitor the air pressure in your vehicle’s tires and transmit 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. A Driver Information Center (DIC) message to check the pressure in a specific tire will also appear on the DIC display. The low tire pressure warning symbol on the instrument panel cluster and the CHECK TIRE PRESSURE message on the DIC display will appear at each ignition cycle until the tires are inflated to the correct inflation pressure. For additional information and details about the DIC operation and displays see DIC Controls and Displays on page 233 and DIC Warnings and Messages on page 239. You may notice, during cooler weather conditions, that the low tire pressure warning symbol and the CHECK TIRE PRESSURE message will

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display when the vehicle is first started and then turn off as you start to drive the vehicle. This could be an early indicator that the tire pressures are getting low and need to be checked and inflated to the proper pressure. 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. A Tire and Loading Information Label, attached to your vehicle, shows the size of your vehicle’s original tires and the correct inflation pressure for your vehicle’s tires when they are cold. See Loading Your Vehicle on page 327, for the location of the Tire and Loading Information label. Also see Inflation - Tire Pressure on page 402. Your vehicle’s TPMS can alert you about a low tire pressure condition but it does not replace normal tire maintenance. See Tire Inspection and Rotation on page 410 and Tires on page 394. Notice: Do not use a tire sealant if your vehicle has Tire Pressure Monitors. The liquid sealant can damage the tire pressure monitor sensors.

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Resetting the TPMS Sensor Identification Codes Each TPMS sensor has a unique identification code. Any time you replace one or more of the TPMS sensors, rotate the vehicle’s tires, or install a full-size spare that has a TPMS sensor, the sensor’s identification codes will need to be matched to the new tire/wheel position. Each tire/wheel position is matched to the TPMS sensor using a TPMS diagnostic tool. See your GM dealer for service. The TPMS sensors may also be matched to each tire/wheel position by increasing or decreasing the tire’s air pressure. When increasing the tire’s air pressure, do not exceed the maximum tire pressure indicated on the tire’s sidewall. You will 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 will need to start over.

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

engine off.

3. Press the Driver Information Center (DIC)

vehicle information button until the RELEARN TIRE POSITIONS displays.

4. Press the set/reset button to allow the system to learn the tire positions. The horn will sound twice to indicate that the TPMS is ready, and then the message TIRE LEARNING ACTIVE will display. The sensor matching process can begin.

5. Start with the driver’s side front tire. 6. Remove the valve cap from the valve 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, confirms that the sensor identification code has been matched to this tire position. To decrease the tire’s air-pressure use the pointed end of the valve cap, a pencil-style air pressure gage or a key.

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7. Proceed to the passenger’s side front tire,

and repeat the procedure in Step 6.

8. Proceed to the passenger’s side rear tire,

and repeat the procedure in Step 6.

9. Proceed to the driver’s side rear tire, and

repeat the procedure in Step 6.

10. After hearing the confirming horn chirp for the driver’s side rear tire, the tire learning process ends. Turn the ignition switch to OFF.

11. Set all four tires to the recommended air

pressure level as indicated on the Tire and Loading Information label.

12. Put the valve caps back on the valve stems. The compact spare tire does not have a TPMS sensor. If you replace one of the road tires with the compact spare, the SERVICE TIRE MONITOR SYSTEM message will be displayed on the DIC screen. This message should go off once you re-install the road tire containing the TPMS sensor.

Federal Communications Commission (FCC) and Industry and Science Canada This device 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.

This device complies with RSS-210 of Industry 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 Inspection and Rotation Tires should be rotated every 5,000 to 8,000 miles (8 000 to 13 000 km). 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 411 and Wheel Replacement on page 416 for more information. The purpose of regular rotation is to achieve more uniform wear for all tires on the vehicle. The first rotation is the most important. See Scheduled Maintenance on page 457.

Four-Tire Rotation Pattern

If your vehicle has a compact spare tire, it should not be included in the tire rotation process. Use the four-tire rotation pattern shown. 410

Five-Tire Rotation Pattern

A five-tire rotation pattern may be used for your professional vehicle, if it has a full-size spare tire and wheel assembly that matches the original equipment tires and wheels in size, type and brand. The correct five-tire rotation pattern is shown. After the tires have been rotated, adjust the front and rear inflation pressures as shown on the Tire and Loading Information label. See Loading Your Vehicle on page 327.

Vehicles that have the Tire Pressure Monitor System (TPMS) will need to have the sensors reset after a tire rotation is performed. See Tire Pressure Monitor System on page 406. Make certain that all wheel nuts are properly tightened. See “Wheel Nut Torque” under Capacities and Specifications on page 452.

{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 420.

When It Is Time for New Tires

One way to tell when it is time for new tires is to check the treadwear indicators, which will appear when your tires have only 1/16 inch (1.6 mm) or less of tread remaining.

You need a new tire if any of the following statements are true: (cid:127) You can see the indicators at three or more

places around the tire.

(cid:127) You can see cord or fabric showing through

the tire’s rubber.

(cid:127) The tread or sidewall is cracked, cut, or

snagged deep enough to show cord or fabric.

(cid:127) The tire has a bump, bulge, or split. (cid:127) The tire has a puncture, cut, or other damage

that cannot be repaired well because of the size or location of the damage.

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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. 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 by the tire manufacturer. If the tires have an all-season tread design, the TPC spec number will be followed by an MS for mud and snow. See Tire Sidewall Labeling on page 395 for additional information.

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{CAUTION:

Mixing tires could cause you to lose control of your vehicle 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 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 all wheels. Your vehicle may have a compact spare tire and wheel assembly. If the vehicle has a compact spare tire and wheel, they have the same overall diameter as your vehicle’s full-size tires and wheels. Because they were designed and developed for use on your vehicle, it is all right to drive your vehicle with the compact spare installed properly. Compact spare tires are designed for temporary use only. See Spare Tire on page 430.

{CAUTION:

If you use bias-ply tires on your 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 your 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.

Vehicles that have a tire pressure monitoring system may 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 406. Your vehicle’s original equipment tires are listed on the Tire and Loading Information label. This label is attached to the vehicle’s center pillar (B-pillar). See Loading Your Vehicle on page 327.

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Different Size Tires and Wheels If you add wheels or tires that are a different size than your original equipment wheels and tires, this may 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, 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.

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See Buying New Tires on page 412 and Accessories and Modifications on page 347 for additional information.

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.

Warning: The traction grade assigned to this tire is based on straight-ahead braking traction tests, and does not include acceleration, cornering, hydroplaning, or peak traction characteristics. 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. Warning: 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.

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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 may need to be checked. If you notice your vehicle vibrating when driving on a smooth road, your tires and wheels may need to be rebalanced. See your dealer 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. Some aluminum wheels can sometimes be repaired. See your GM dealer if any of these conditions exist. Your GM dealer will know the kind of wheel you need. 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 your wheels, wheel bolts or wheel nuts, replace them only with new GM original equipment parts. This way, you will be sure to have the right wheel, wheel bolts and wheel nuts for your vehicle.

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{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.

If your vehicle is a professional model, the wheels have a unique offset and bolt hole diameter. Each of the wheels on the professional vehicle have eight wheels nuts. The wheels on the non-professional vehicle have five wheel nuts. See Changing a Flat Tire on page 420 for more information. Used Replacement Wheels

{CAUTION:

Putting a used wheel on your 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:

Do not use tire chains. 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.

CAUTION:

(Continued)

CAUTION:

(Continued)

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. 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 front tires.

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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 will create 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. The jack provided with your vehicle 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. Use the jack provided with your vehicle only 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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CAUTION:

(Continued)

3. Turn off the engine and do not restart

while the vehicle is raised.

4. Do not allow passengers to remain

in the vehicle.

To be even more certain the vehicle will not move, you should put 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.

Changing a Flat Tire If a tire goes flat, avoid further tire and wheel damage by driving slowly to a level place. Turn on your vehicle’s hazard warning flashers. See Hazard Warning Flashers on page 158 for more information.

{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 PARK (P).

CAUTION:

(Continued)

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

Removing the Spare Tire and Tools The equipment you will need is in the trunk. To access the equipment, do the following: 1. Open the trunk. See Trunk on page 102

for more information.

The following information will tell you next how to use the jack and change a tire.

2. Press the area at

the front of the handle located on the cover so that the back edge raises.

3. Grab the handle and

remove the cover.

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4. Turn the wing nut to remove the retainer that

holds the wrench and jack.

5. Remove the wheel wrench, jack and

spare tire from the trunk. See Spare Tire on page 430 for more information.

The tools you will be using include the jack (A) and the wheel wrench (B).

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Removing the Flat Tire and Installing the Spare Tire

2. For models with exposed lug nuts, loosen

them using the wheel wrench. Do not remove them yet.

1. For models having aluminum wheels with a

center wheel cover, use the flat end of the wheel wrench to gently pry the wheel covers off. Be careful not to scratch the aluminum wheel edge and do not try to remove it with your hands. Then loosen the wheel nuts with the wheel wrench. Do not remove them yet.

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{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.

3. Find the jacking location from the diagram above and use the corresponding cutouts located in the plastic molding. The front location is (A) 8.5 inches (21 cm) from the rear edge of the front wheel well, and the rear location (B) is 3.5 inches (8.5 cm) from the front edge of the rear wheel well. The notches may also be labeled JACK with an arrow pointing to the jacking location on the vehicle.

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6. Put the spare tire near you.

If you position the jack under the

Notice: rocker molding and attempt to raise the vehicle, you could break the molding and/or cause other damage to your vehicle. Always position the jack so that when the jack head is raised, it will fit firmly in the notch located inboard from the rocker molding. 4. Turn the jack handle counterclockwise to

lower the jack lift head until the jack fits under the vehicle.

7. Raise the vehicle by turning the jack handle clockwise. Raise the vehicle far enough off the ground for the spare tire to fit under the vehicle.

8. Remove all wheel nuts and take off the

flat tire.

5. Raise the jack until the metal flange fits firmly

into the channel of the jack head.

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{CAUTION:

Rust or dirt on the wheel, or on the parts to which it is fastened, can make the 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 the 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.

9. Remove any rust or dirt from the wheel bolts, mounting surfaces, and spare wheel.

10. Place the spare tire on the wheel-mounting

surface.

{CAUTION:

Never use oil or grease on studs or nuts. If you do, the nuts might come loose. Your wheel could fall off, causing a serious accident.

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11. Put the wheel nuts

back on with the rounded end of the nuts toward the