2008 Chevrolet Cobalt Owners Manual

3. Turn on your heater to full hot at the highest 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 and you have not stopped, pull over, stop, and park your vehicle right away. If there is still no sign of steam, you can 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. You may decide not to lift the hood but to get service help right away.

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(cid:127) (cid:127) Cooling System When you decide it is safe to lift the hood, here is what you will see:

{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.

2.2L L4 Engine shown, 2.4L L4 Engine similar

A. Electric Engine Cooling Fan B. Coolant Surge Tank and Pressure Cap

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The coolant level should be at the COLD FILL line. If it is not, you may have a leak at the pressure cap or in the radiator hoses, heater hoses, radiator, water pump, or somewhere in the cooling system.

{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 your vehicle is equipped with the 2.2L or 2.4L L4 engine and there seems to be no leak, with the engine on, check to see if the electric engine cooling fan is running. If the engine is overheating, the fan should be running. If it is not, your vehicle needs service.

Notice: Engine damage from running the engine without coolant is not covered by the warranty. 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 the warranty. Always use DEX-COOL® (silicate-free) coolant in the vehicle.

How to Add Coolant to the Coolant Surge Tank Notice: This vehicle has a specific coolant fill procedure. Failure to follow this procedure could cause your engine to overheat and be severely damaged. If you have not found a problem yet, check to see if coolant is visible in the coolant surge tank. If coolant is visible but the coolant level is not at the COLD FILL line, add a 50/50 mixture of clean, drinkable water and DEX-COOL® coolant at the coolant surge tank, but be sure the cooling system, including the coolant surge tank pressure cap, is cool before you do it. See Engine Coolant on page 5-20 for more information.

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2.2L and 2.4L L4 Engines If no coolant is visible in the coolant surge tank, add coolant as follows:

{CAUTION:

{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.

Adding only plain water to the cooling system can be dangerous. Plain water, or some other liquid such as alcohol, can boil before the proper coolant mixture will. The vehicle’s coolant warning system is set for the proper coolant mixture. With plain water or the wrong mixture, the engine could get too hot but you would not get the overheat warning. The 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 crack

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

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2. Then keep turning the

pressure cap slowly, and remove it.

{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.

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 about two or two and one-half turns. If you hear a hiss, wait for that to stop. This will allow any pressure still left to be vented out the discharge hose.

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4. With the coolant surge tank pressure 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 fan. By this time, the coolant level inside the coolant surge tank may be lower. If the level is lower than the COLD FILL line, add more of the proper mixture to the coolant surge tank until the level reaches the COLD FILL line.

5. Then replace the pressure cap. Be sure the pressure cap is hand-tight and fully seated. See your dealer/retailer, if necessary.

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3. Fill the coolant surge tank with the proper mixture,

to the COLD FILL line on the tank. Wait about five minutes, then check to see if the level is below the COLD FILL line. If the level is below the line, add additional coolant to bring the level up to the line. Repeat this procedure until the level remains constant at the COLD FILL line for at least five minutes.

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

Open the cap with the washer symbol on it. Add washer fluid until the tank is full. See Engine Compartment Overview on page 5-12 for reservoir location.

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. Fill the washer fluid tank only three-quarters full when it is very cold. This allows for fluid 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 the vehicle’s windshield washer system and paint.

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(cid:127) Brakes Brake Fluid

The brake master cylinder and, on manual transmission vehicles, the clutch hydraulic system use the same reservoir. The reservoir is filled with DOT-3 brake fluid.

See Engine Compartment Overview on page 5-12 for the location of the reservoir. 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 and/or clutch hydraulic system. If it is, you should have the brake and/or clutch hydraulic system fixed, since a leak means that sooner or later the brakes and/or clutch will not work well.

It is not a good idea to top off the brake/clutch fluid. Adding fluid will not correct a leak. If fluid is added when the brake linings are worn, there will be too much fluid when new brake linings are installed. Add or remove fluid, as necessary, only when work is done on the brake/clutch 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 and/or clutch hydraulic system.

When the brake fluid falls to a low level, the brake warning light will come on. See Brake System Warning Light on page 3-31.

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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 6-12. Always clean the brake fluid reservoir cap and the area around the cap before removing it. This helps keep dirt from entering the reservoir.

{CAUTION:

With the wrong kind of fluid in the brake or clutch hydraulic system, the brakes or clutch might not work well. This could cause a crash. Always use the proper brake fluid.

Notice: (cid:127) Using the wrong fluid can badly damage brake or clutch hydraulic system parts. For example, just a few drops of mineral-based oil, such as engine oil, in the brake or clutch hydraulic system can damage brake or clutch hydraulic 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 5-99.

Brake Wear Your vehicle has front disc brakes and could have rear drum brakes or rear 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 can 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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(cid:127) {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 can cause a brake squeal when the brakes are first applied or lightly applied. This does not mean something is wrong with the 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 torque specifications in Capacities and Specifications on page 5-112. If your vehicle has rear drum brakes, they do not have wear indicators, but if you ever hear a rear brake rubbing noise, have the rear brake linings inspected immediately. Also, the rear brake drums should

be removed and inspected each time the tires are removed for rotation or changing. When you have the front brake pads replaced, have the rear brakes inspected, too. Brake linings should always be replaced as complete axle sets. Brake Pedal Travel See your dealer/retailer 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 that brake service might be required. Brake Adjustment Every time you make a moderate brake stop, the disc brakes adjust for wear. If you rarely make a moderate or heavier stop, then the brakes might not adjust correctly. If you drive in that way, then — very carefully — make a few moderate brake stops about every 1,000 miles (1 600 km), so the brakes will adjust properly. If your vehicle has rear drum brakes and the brake pedal goes down farther than normal, the rear drum brakes might need adjustment. Adjust them by backing up and firmly applying the brakes a few times.

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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 brake parts. When you replace parts of the braking system — for example, when the brake linings wear down and you need new ones put in — be sure you get new approved replacement parts. If you do not, the brakes might not work properly. For example, if someone puts in brake linings that are wrong for your vehicle, the balance between the 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. Battery Your vehicle has a maintenance free battery. When it is time for a new battery, see your dealer/retailer for one that has the replacement number shown on the original battery’s label. Your vehicle’s battery is located in the trunk. You do not need to access the battery to jump start your vehicle. See Jump Starting on page 5-34. 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.

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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 5-34 for tips on working around a battery without getting hurt.

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

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 or ignite. (cid:127) They contain enough electricity to burn you.

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

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 transmission in PARK (P) or a manual transmission in NEUTRAL before setting the parking brake.

Ignoring these steps could result in costly

Notice: 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 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.

If you leave your radio or other accessories

Notice: 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 outlet. 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!

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4. Open the hood on the other vehicle and locate

the positive (+) and negative (−) terminal locations on that vehicle. You will not see the battery of your vehicle under the hood. It is located in the trunk. You will not need to access your battery for jump starting. Your vehicle has a remote positive (+) and a remote negative (−) jump starting terminal.

The remote positive terminal is located under a red tethered cap on the engine compartment fuse block. Lift the cap to access the terminal.

The remote negative (−) ground terminal, marked GND (−), is located behind the engine coolant surge tank.

See Engine Compartment Overview on page 5-12
for more information on the location of the positive (+) and negative (−) terminals on your vehicle.

{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.

5-36

{CAUTION:

{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 don’t, 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.

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 positive (+)

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

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7. 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.

8. 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. 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.

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.

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If the jumper cables are connected or

Notice: 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.

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 positive (+) terminal cover to its

original position.

Headlamp Aiming The optical headlamp aiming system has been preset at the factory and should need no further adjustment However, If the vehicle is damaged in a crash, 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/retailer for service if the headlamps need to be re-aimed. It is possible however, to re-aim the headlamps as described. The vehicle should: (cid:127) Be placed so the headlamps are 25 ft. (7.6 m)

from a light colored wall.

(cid:127) Have all four tires on a perfectly level surface

which is level all the way to the wall.

(cid:127) Be placed so it is perpendicular to the wall. (cid:127) Not have any snow, ice, or mud on it. (cid:127) Be fully assembled and all other work stopped

while headlamp aiming is being done.

(cid:127) Have a full tank of fuel and one person or

160 lbs (75 kg) on the driver seat.

(cid:127) Have all tires properly inflated. 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 on the headlamps:

1. Open the hood. See Hood Release on page 5-11

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.

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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. Do not place it directly on the headlamp. This allows only the beam of light from the headlamp being adjusted to be seen on the flat surface.

7. Locate the vertical headlamp aiming screws, which are under the hood near each headlamp assembly. The adjustment screw can be turned with a 6 mm socket wrench.

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.

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.

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Headlamps, Front Turn Signal, Sidemarker, and Parking Lamps

Bulb Replacement For the proper type of replacement bulbs, see Replacement Bulbs on page 5-47. 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.

A. Front Turn Signal/Parking Lamp B. Sidemarker C. Headlamp

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To replace one of these bulbs: 1. Open the hood. See Hood Release on page 5-11

for more information.

2. Remove the two hex bolts from the headlamp

assembly.

3. Remove the two plastic fasteners from the fascia. 4. Pull the front fascia back.

You might need someone else to assist you with Steps 3 and 4.

5. Pull the headlamp assembly up on an angle and

towards the radiator to remove it.

6. Disconnect the bulb base from the wiring harness

by lifting the plastic locking tab.

7. To replace a headlamp bulb, do the following: 7.1. Disconnect the wiring harness from the

bulb socket.

7.2. Remove the black retainer by turning it

counterclockwise.

8. Turn the bulb socket for the headlamp, front turn signal, or parking lamp counterclockwise. For the sidemarker bulb, use a tool to assist in turning the bulb socket.

9. Pull the old bulb out of the socket. 10. Install a new bulb. 11. Reinstall the bulb assembly by reversing Steps 1

through 8. When reinstalling the headlamp assembly, first make sure that the wiring harness is in its original position. If not, the headlamp assembly will not fit correctly. Align the two tabs on the bottom of the assembly that fit into two slots in the headlamp assembly bracket.

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Center High-Mounted Stoplamp (CHMSL) To replace a CHMSL bulb: 1. Open the trunk. See Trunk on page 2-13 for

more information.

2. Locate the CHMSL bulb assembly in the trunk lid. 3. Press the plastic tabs to release the bulb assembly.

5. Remove the bulb by pulling it straight out. 6. Install a new bulb. 7. Align the tabs in the bulb assembly with the

assembly in the trunk lid. Push the bulb assembly back into place until it snaps in. You may need to use a tool to guide the tabs into the assembly.

Taillamps and Turn Signal Lamps (Coupe)

4. Pull the bulb assembly down to access the bulbs.

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To replace this bulb: 1. Open the trunk. See Trunk on page 2-13 for

more information.

2. Remove the fastener which holds down the

trunk trim.

3. Disconnect the wiring harness by lifting up on the

tab to release and pull it straight out.

4. Remove the taillamp bulb socket from the assembly

by turning it counterclockwise.

5. Pull the old bulb out of the socket. 6. Install a new bulb. 7. Reverse Steps 1 through 4 to reinstall the taillamp

assembly.

Taillamps, Turn Signal, Stoplamps and Back-up Lamps (Sedan) To replace one of these bulbs: 1. Open the trunk. See Trunk on page 2-13 for

more information.

2. Remove the fastener which holds down the trunk trim. Once you have removed the trim, there will be one more fastener to remove.

3. Remove the outer two screws from the taillamp

assembly.

4. Disconnect the wiring harness by lifting up on

the tab to release and pull it straight out.

5. Remove the taillamp from the quarter panel.

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

6. Locate the bulb to change. 7. Remove the taillamp bulb socket from the assembly

by turning it counterclockwise.

8. Pull the old bulb out of the socket. 9. Install a new bulb. 10. Reverse Steps 1 through 6 to reinstall the taillamp

assembly.

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Back-Up Lamps (Coupe)

To replace a back-up lamp bulb: 1. Open the trunk. See Trunk on page 2-13 for

more information.

2. Locate the back-up lamp bulb assembly in

the trunk lid.

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3. Remove the bulb socket by turning it

counterclockwise. On vehicles that have a back-up lamp cover, first remove it by depressing the tab at the top.

4. Pull out the old bulb. 5. Install a new bulb. 6. Reinstall the bulb socket by aligning the tabs and

turning it clockwise to secure.

License Plate Lamp To replace one of these bulbs:

Replacement Bulbs

Exterior Lamps

Bulb Number

Back-Up Lamps

Center High-Mounted Stoplamp (CHMSL)

Front Parking/Turn Signal Lamps

Halogen Headlamps, High/Low-Beam

License Plate Lamp and Sidemarker

Stoplamp, Taillamp and Turn Signal Lamps

921

912

3157KX

9007 LL

194

3057KX

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

5-47

1. Remove the two screws holding each of the license

plate lamps.

2. Turn and pull the license plate lamp toward you

through the opening.

3. Turn the bulb socket counterclockwise and pull the

bulb straight out of the socket.

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

plate lamp.

Windshield Wiper Blade Replacement Windshield wiper blades should be inspected for wear or cracking. See Scheduled Maintenance on page 6-4 for more information on wiper blade inspection. Replacement blades come in different types and are removed in different ways. For proper type and length, see Maintenance Replacement Parts on page 6-14.

Here is how to remove the wiper blades: 1. Pull the windshield wiper arm away from the

windshield.

2. Push the release lever and slide the wiper assembly

toward the driver side of the vehicle.

3. Install a new blade by reversing Steps 1 and 2.

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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.

{CAUTION:

Poorly maintained and improperly used tires are dangerous.

(cid:127) 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 Your Vehicle on page 4-27.

CAUTION:

(Continued)

CAUTION:

(Continued)

(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. Tire pressure should be checked when your vehicle’s tires are cold. See Inflation - Tire Pressure on page 5-56.

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

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(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. If your vehicle has 205/55R16 size tires, they meet the GM TPC Spec rating, but the TPC Spec code has not been molded onto the tire’s sidewall. (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.

Tire Sidewall Labeling Useful information about a tire is molded into its sidewall. The examples below show a typical passenger vehicle tire and a compact spare tire sidewall.

Passenger (P-Metric) Tire Example

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(D) Tire Identification Number (TIN): The letters and numbers following DOT (Department of Transportation) code is 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 5-68. (G) Maximum Cold Inflation Load Limit: Maximum load that can be carried and the maximum pressure needed to support that load.

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. If your vehicle has a compact spare tire, see Compact Spare Tire on page 5-94 and If a Tire Goes Flat on page 5-73.

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(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 letters and numbers following the DOT (Department of Transportation) code is 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. (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 5-56. (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.

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(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. Tire Size The following illustration shows an example of a typical passenger vehicle tire size.

(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. A tire size without the letter P as the first character is certified to European standards.

(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.

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 5-56.

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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 Your Vehicle on page 4-27. GAWR FRT: Gross Axle Weight Rating for the front axle. See Loading Your Vehicle on page 4-27. GAWR RR: Gross Axle Weight Rating for the rear axle. See Loading Your Vehicle on page 4-27. 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.

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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 Your Vehicle on page 4-27. 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 5-56 and Loading Your Vehicle on page 4-27. 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 5-65. 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 5-68. 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 4-27. 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 4-27.

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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:127) Too much flexing (cid:127) Too much heat (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 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 Your Vehicle on page 4-27. 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 compact spare tire, it should be at 60 psi (420 kPa). For additional information regarding the compact spare tire, see Compact Spare Tire on page 5-94.

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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 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). 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.

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.

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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 5-59 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.

The Tire Pressure Monitor System (TPMS) operates on a radio frequency and complies 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.

Tire Pressure Monitor Operation The Tire Pressure Monitor System (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 turns on the low tire pressure warning light 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. Using the DIC, 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 on page 3-40
and DIC Warnings and Messages on page 3-43. 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 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 Your Vehicle on page 4-27, for an example of the Tire and Loading Information label and its location on your vehicle. Also see Inflation - Tire Pressure on page 5-56. Your vehicle’s TPMS system can warn you about a low tire pressure condition but it does not replace normal tire maintenance. See Tire Inspection and Rotation on page 5-63 and Tires on page 5-49. 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.

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(cid:127) 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:127) 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 5-66.

(cid:127) 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 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:127) 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:127) TPMS Sensor Matching Process Each TPMS sensor has a unique identification code. Any time you replace one or more of the TPMS sensors or rotate the vehicle’s tires, the identification codes need to be matched to the new tire/wheel location. The sensors are matched, to the tire/wheel locations, 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. When increasing the tire’s pressure, do not exceed the maximum inflation pressure indicated on the tire’s sidewall. To decrease the tire’s air-pressure use the pointed end of the valve cap, a pencil-style air pressure gage, or a key. You have two minutes to match each tire and wheel position. If it takes longer than two minutes to match any tire and wheel position, the matching process stops and you need to start over.

TPMS Matching Process for Vehicles with Remote Keyless Entry (RKE) 1. Set the parking brake. 2. Turn the ignition switch to ON/RUN with the

engine off.

3. Press and hold the Remote Keyless Entry (RKE) transmitter’s LOCK and UNLOCK buttons, at the same time, for about five seconds to start the TPMS learn mode. The horn sounds twice indicating the TPMS receiver is ready and in learn mode.

4. Start with the driver side front tire. The driver side

front turn signal also comes on to indicate that corner’s sensor is ready to be learned.

5. Remove the valve cap from the tire’s valve stem.

Activate the TPMS sensor by increasing or decreasing the tire’s air pressure for about eight seconds. The horn chirp, can take up to 30 seconds to sound. It chirps one time and then all the turn signals flash one time to confirm the sensor identification code has been matched to the tire/wheel position.

6. The passenger side front turn signal comes on to indicate that corner sensor is ready to be learned. Proceed to the passenger side front tire and repeat the procedure in Step 5.

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7. The passenger side rear turn signal comes on to indicate that corner sensor is ready to be learned. Proceed to the passenger side rear tire and repeat the procedure in Step 5.

8. The driver side rear turn signal comes on to

indicate that corner sensor is ready to be learned. Proceed to the driver side rear tire, and repeat the procedure in Step 5.

9. After hearing the single horn chirp for the driver side rear tire, two additional horn chirps sound to indicate the tire learning process is done. Turn the ignition switch to LOCK/OFF. If no tires are learned after entering the TPMS learn mode, or if communication with the receiver stops, or if the time limit has expired, turn the ignition switch to LOCK/OFF and start over beginning with Step 2.

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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TPMS Matching Process for Vehicles without Remote Keyless Entry (RKE) 1. Set the parking brake. 2. Turn the ignition switch to ON/RUN with the

engine off.

3. Using the Driver Information Center (DIC), press

the INFO and Set/Reset buttons at the same time for about one second. Then press and release the INFO button until the TIRE LEARN? message displays.

4. Press and hold the Set/Reset DIC button for

approximately three seconds to start the TPMS learn mode. The horn sounds twice to indicate the TPMS receiver is ready and the TIRE LEARN ON message displays. The driver side front turn signal also comes on to indicate that corner sensor is ready to be learned.

5. Start with the driver side front tire. 6. Remove the valve cap from the tire’s valve stem.

Activate the TPMS sensor by increasing or decreasing the tire’s air pressure for about eight seconds. The horn chirp, can take up to 30 seconds to sound. It chirps one time and then all the turn signals flash one time to confirm the sensor identification code has been matched to the tire/ wheel position.

7. The passenger side front turn signal comes on to indicate that corner sensor is ready to be learned. Proceed to the passenger side front tire and repeat the procedure in Step 6.

8. The passenger side rear turn signal comes on to indicate that corner sensor is ready to be learned. Proceed to the passenger side rear tire and repeat the procedure in Step 6.

9. The driver side rear turn signal comes on to

indicate that corner sensor is ready to be learned. Proceed to the driver side rear tire, and repeat the procedure in Step 6.

10. After hearing the single horn chirp for the driver

side rear tire, two additional horn chirps sound to indicate the tire learning process is done. The LEARN COMPLETE message displays if all four tire positions are learned. Turn the ignition switch to LOCK/OFF. If no tires are learned after entering the TPMS learn mode, or if communication with the receiver stops, or if the time limit has expired, the TIRE LEARN? message displays on the DIC. Turn the ignition switch to LOCK/OFF and start over beginning with Step 2.

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.

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 5-65 for more information. Tires should be rotated every 5,000 to 8,000 miles (8 000 to 13 000 km). See Scheduled Maintenance 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.

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Any time you notice unusual wear, rotate the 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 5-65 and Wheel Replacement on page 5-70.

Reset the Tire Pressure Monitor System. See Tire Pressure Monitor Operation on page 5-59. Make certain that all wheel nuts are properly tightened. See “Wheel Nut Torque” under Capacities and Specifications on page 5-112.

{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 5-74.

When rotating the vehicle’s tires, always use the correct rotation pattern shown here. Do not include the compact spare tire in the tire rotation. 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 5-56
and Loading Your Vehicle on page 4-27.

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

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 will appear when your tires have only 1/16 inch (1.6 mm) or less of tread remaining.

You need new tires 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.

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(cid:127) (cid:127) (cid:127) 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 near the tire size. 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 5-50 for additional information.

GM recommends replacing tires in sets of four. 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 5-63
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 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. It is all right to drive with your compact spare temporarily, as it was developed for use on your vehicle. See Compact Spare Tire on page 5-94.

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{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 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 5-57. Your vehicle’s original equipment tires are listed on the Tire and Loading Information Label. See Loading Your Vehicle on page 4-27, for more information about the Tire and Loading Information Label and its location on your vehicle.

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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.

See Buying New Tires on page 5-66 and Accessories and Modifications on page 5-3 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. 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 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. 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, 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 your vehicle.

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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.

{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. See Changing a Flat Tire on page 5-74 for more information.

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If your vehicle has a tire size other than

Notice: P205/55R16 or P205/50R17 size tires, use tire chains only where legal and only when you must. Use only SAE Class S-type chains that are the proper size for your tires. Install them on the front tires and 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.

Tire Chains

{CAUTION:

If your vehicle has P205/55R16 or P205/50R17
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. 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 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. 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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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 hazard warning flashers.

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{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 an automatic transmission shift lever

in PARK (P), or shift a manual transmission to FIRST (1) or REVERSE (R).

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.

When you have 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 located in the trunk. Base Models 1. Open the trunk. See Trunk on page 2-13 for more

information.

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

2. Lift the trunk liner to access the spare tire and tools.

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A. Cover B. Retainer C. Spare Tire D. Wing Nut E. Jack and Wheel Wrench F. Bolt

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3. Remove the retainer (B) that holds down the

spare tire. See Compact Spare Tire on page 5-94
for more information.

4. Remove the spare tire (C) by gently pulling it

up and out of the trunk.

5. Remove the wing nut (D) that holds the jack and

remove the jack and wheel wrench (E).

Uplevel Models 1. Open the trunk. See Trunk on page 2-13 for

more information.

2. Lift the trunk liner to access the spare tire

and tools.

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A. Retainer B. Jack and Wheel Wrench C. Spare Tire D. Foam Support E. Bolt 3. Remove the retainer (A) that holds down the jack,

wheel wrench (B) and spare tire (C).

4. Remove the spare tire by gently pulling it up and

out of the trunk.

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

You will need to turn the plastic wheel nut counterclockwise to loosen the wheel wrench from the jack.

Press the button and then pull on the end of the wheel wrench to extend the handle.

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Removing the Flat Tire and Installing the Spare Tire (Sport Model) Sport Model Only The Sport Model has larger performance brakes than the Base Model. The compact spare tire will not clear the front brakes. Do not use the compact spare tire in the event of a front flat tire. You must use the rear tire to replace the front flat tire.

To change the rear road tire: Rear Tire Changing Procedure 1. Do a safety check before proceeding. See Changing

a Flat Tire on page 5-74 for more information.

2. If your vehicle has plastic wheel covers, use the

wheel wrench to loosen the plastic wheel nut caps. Once the plastic wheel nut caps have been loosened with the wheel wrench, you can finish loosening them with your fingers. The plastic nut caps do not come off.

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3. Using the flat end of the wheel wrench, pry along the edge of the rear wheel cover until it comes off. Store the wheel cover in the trunk until the flat tire is repaired or replaced.

4. Use the wheel wrench to loosen all the rear wheel

nuts. Do not remove them yet.

Notice: Make sure that the jack lift head is in the correct position or you may damage your vehicle. The repairs would not be covered by your warranty.

5. Position the jack lift head at the rear jack location

nearest the rear tire. The rear location is about 4 inches (10 cm) in front of the rear wheel opening.

6. Raise the jack head until it fits firmly in the vehicle’s frame, where the notch is located, nearest the flat tire.

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8. Raise the vehicle by turning the jack handle

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

9. Remove all of the

wheel nuts.

7. Put the compact spare tire near the rear 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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11. Remove any rust or dirt

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

Reinstall the wheel nuts with the rounded end of the nuts toward the wheel. Tighten each nut by hand until the wheel is held against the hub.

12. Lower the vehicle by turning the jack handle counterclockwise. Lower the jack completely.

{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 5-74.

10. Place the compact spare tire on the wheel-mounting

surface.

{CAUTION:

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

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{CAUTION:

Incorrect or improperly tightened wheel nuts can cause the wheel to come loose and even come off. This could lead to a crash. If you have to replace them, be sure to get new original equipment wheel nuts. Stop somewhere as soon as you can and have the nuts tightened with a torque wrench to the proper torque specification. See Capacities and Specifications on page 5-112 for wheel nut torque specification.

Improperly tightened wheel nuts can lead

Notice: 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 5-112 for the wheel nut torque specification.

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5-Wheel Nuts

13. Tighten the wheel nuts firmly in a crisscross

sequence, as shown.

Notice: Wheel covers will not fit on your vehicle’s compact spare. If you try to put a wheel cover on the compact spare, the cover or the spare could be damaged.

To change the front flat tire: Front Flat Tire Changing Procedure: 1. Perform a rear tire change by removing the rear tire

and installing the compact spare tire in the rear wheel location. The rear road tire will be used to replace the front flat tire. See Rear Tire Changing Procedure in this section.

2. Do a safety check before proceeding. See Changing

a Flat Tire on page 5-74.

3. If your vehicle has plastic wheel covers, use the

wheel wrench to loosen the plastic wheel nut caps. Once the plastic wheel nut caps have been loosened with the wheel wrench, you can finish loosening them with your fingers. The plastic nut caps do not come off.

4. Using the flat end of the wheel wrench, pry along

the edge of the wheel cover until it comes off. Store the wheel cover in the trunk until the flat tire is repaired or replaced.

5. Use the wheel wrench to loosen all the wheel nuts

on the flat tire. 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.

9. Raise the vehicle by turning the jack handle

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

6. Position the jack lift head at the jack location

nearest the flat tire. The front location is about 8 inches (20 cm) behind the front wheel opening. Notice: Make sure that the jack lift head is in the correct position or you may damage your vehicle. The repairs would not be covered by your warranty. 7. Raise the jack head until it fits firmly in the