Introduction
Tires are designed and built with great care to provide thousands of miles of excellent service. But for maximum benefit they must be maintained properly.
The most important factors in tire care are:
- Proper inflation pressure
- Proper vehicle loading
- Proper tire wear
- Regular inspection
- Good driving habits
- Vehicle conditions
For additional tire safety related information:
Rubber Manufacturers Association (RMA)
National Highway Traffic Safety Administration (NHTSA)
Tire Inspection
In addition to performing regular maintenance, you must also keep an eye out for potential problems that might affect your tires. Regular inspections can help you prevent tire trouble, and keep you rolling safely down the road.
When inspecting your tires, look for:
Uneven tread wear - This can include more wear on one tread edge than the other, a rippled pattern of high and low wear, or exposed steel wire. Uneven wear can be caused by problems such as underinflation, misalignment and improper balancing.
Shallow tread - Bald tires to skid and slide on pavement, and are more likely to be damaged by potholes and other road hazards. The tread on your tires should be at least 1/16 of an inch deep. If it isn't, the tire must be replaced. To help you see tread problems, tires have a built in "tread wear indicators." These are narrow bars of smooth rubber that run across the tread. When the tread is even with the bars, it is worn down to the minimum level and must be replaced immediately.
You can also perform a simple test using a US penny. Put the edge of the coin in to the tread, with Lincoln going in head first. If the top of Lincoln's heads is covered by tread, that's good. If the top of his head I is entirely visible, it's time to replace the tire.
Troublemakers - Check for small stones, pieces of glass, bits of metal and other foreign objects that might be wedged into the tread, and carefully pick them out. They can cause serious problems if they are pushed farther into your tire as you drive.
Damaged areas - Cracks, cuts, splits, punctures, holes and bulges in the tread or on the sides of the tire can indicate serious problems, and the tire may need to be replaced.
Slow leaks - Tires lose some air pressure (about 2 psi) over the course of a month or so, but if you find that you have to add air every few days, have the tire, wheel and valve checked - and if necessary, repair or replace the tire.
Valve caps - Those little caps on your tire's valve stem keep moisture and dirt out, so make sure they are on all your tires. Also, when you have a tire replaced, have a new valve stem assembly installed at the same time.
Driving on a damaged tire can be dangerous. If you see something you're not sure about during your inspection, have it examined by your tire dealer. Any time you see damage to a tire, don't drive on it - use a spare if you need to go somewhere. And finally, pay attention to the "feel" of your tires as you drive. A rough ride may indicate tire damage or excessive wear. If you notice vibrations or other disturbances while driving, and/or you suspect possible damage to your tire or vehicle, immediately reduce speed, drive with caution until you can safely pull off the road and stop, and inspect our tires. If a tire is damaged, deflate it and replace it with your spare. If you do not see any tire damage and cannot identify the source of the vibration, have the vehicle towed to a mechanic or tire dealer for a thorough inspection.
Proper Pressure
Driving on any tire that does not have the correct inflation pressure is dangerous. Proper inflation pressure for your tires may be found in the vehicle owner's manual or the vehicle's tire information placard.
Any underinflated tire builds up excessive heat that may result in sudden tire destruction.
Refer to the tire placard on the vehicle (check vehicle and/or vehicle owners manual for placard location) for the recommended operating inflation pressures. These pressures must be maintained as a minimum. Do not exceed the maximum pressure indicated on the tire sidewall of passenger car tires.
If you are replacing the original size tires with tires of a different size, you must consult a knowledgeable tire dealer to determine the correct inflation pressure for your new tires.
Checking Tire Pressure
Check your tire inflation pressures, including the spare, at least once a month and before going on a long trip. Tire pressure should be measured when tires are cold - that is, they have been driven on. Otherwise, your tires may have heated up, increasing the air pressure inside them by several pounds. This is normal. Never "bleed" or reduce the air pressure in a hot tire.
Failure to maintain correct inflation pressures may result in rapid wear and uneven tread wear, improper vehicle handling and excessive heat buildup which may result in tire failure. (Evidence of air loss or repeated underinflation requires tire removal and expert inspection.)
Tire Inflation with Nitrogen
One of the most important factors in tire care is maintaining proper inflation pressure, regardless of the inflation gas.
Nitrogen is a inert (non-flammable) gas - basically, nothing more than dry air with the oxygen removed (air contains about 78% nitrogen). Nitrogen inflation does not harm tires nor does it affect the warranty.
Proper tire inflation, whether nitrogen or normal air, helps tires wear longer, saves fuel, and helps prevent accidents. Underinflation, regardless of the inflation gas, can make it harder to steer and stop your vehicle, result in loss of vehicle control, cause sudden tire destruction, and lead to serious injury or death.
Nitrogen inflation will not prevent damage or loss of inflation due to road hazards. Nitrogen inflation will also not prevent tire damage due to underinflation, overloading, or off road service. Tire inflation should always be checked and adjusted to the proper inflation pressure on a regular basis (at least monthly and before long trips), regardless of the inflation gas, to provide optimum tire performance.
Wheel Alignment
Wheel alignment and balancing are important for safety and maximum mileage from your tires. Inspect your tires at least once a month for signs of uneven wear or damage (ie. cuts, cracks, splits, penetrations, bulges, and impacts.)
Uneven wear patterns may be caused by improper inflation pressure, misalignment, improper balance or suspension neglect. If not corrected, further tire damage will occur. These conditions shorten the life of your tires and may result in loss of vehicle control and serious personal injury.
You should have your alignment checked periodically as specified by the vehicle owner's manual or whenever you have an indication of trouble such as pulling or vibration.
Rotation
Proper tire rotation is important.
If you notice irregular or uneven tread wear, the tires should be rotated to alleviate the problem. Remember: it is important to check your tires and wheels for signs of possible damage, and check your vehicle for any mechanical problems and correct if necessary.
You should follow the rotation pattern or procedure indicated in your limited warranty and the vehicle owners' manual.
We recommend you rotate tires on front wheel drive vehicles and/or all season tires on any vehicle every 8,000 miles to equalize the rate of wear. You should rotate your tires earlier if signs of irregular or uneven tire wear arise and have the vehicle checked by a qualified technician to determine the cause of the wear condition. the first rotation in the most important.
After rotation, adjust individual tire air pressure to the figures recommended by the vehicle manufacturer for the new locations - front or rear - as shown on the tire placard on the vehicle.
Proper Loading
Do not overload your tires. Driving on any overloaded tire is dangerous.
The maximum load rating of your tires is marked on the tire sidewall. Do not exceed these ratings. Tires which are loaded beyond their maximum allowable loads for the particular application will build up excessive heat that may result in sudden tire destruction.
Do not exceed the gross axle weight ratings for any axle on your vehicle. Consult the vehicle placard and/or vehicle owners manual to determine the gross axle weight rating. Following the loading instructions of the vehicle manufacturer should insure that your tires are not overloaded.
If you are replacing the original size tires with tires of a different size, the replacement tires must have a load carrying capacity equal to or greater than the original equipment tires.
Towing a trailer: If you anticipate towing a trailer, you should see your tire dealer for advice concerning the correct size of tire and inflation pressures. Tire size and air pressure depend upon the type and size of trailer and hitch utilized, but never exceed the maximum cold inflation pressure or the maximum tire load rating. The only sure way to prevent overload is to weigh, axle by axle, the fully-loaded vehicle on a reliable platform scale. Check the tire placard on the vehicle and the owners manual supplied by the manufacturer of your vehicle for further recommendations on trailer towing.
Tire Alterations
Tire alterations are dangerous.
Do not perform any alterations on your tires. Alterations may prevent proper performance, leading to tire damage, which can result in sudden tire destruction. Tires which have been altered are excluded from warranty coverage.
Tire Repairs
For repairs, see any tire dealer at once.
Never use a plug-only or patch-only repair. If any tire has sustained a puncture, have the tire dismounted and inspected internally by any tire dealer for possible damage that may have occurred.
Punctures in the tread of passenger tires which do not exceed 1/4-inch (6mm) in diameter can be repaired by following Rubber Manufacturers' Association (RMA) recommended repair procedures. A plug by itself or a patch by itself is an unacceptable repair. The repair material used - for example, a "combination patch and plug" repair - must seal the innerliner and fill the injury to be considered a permanent repair. Never use a tube in a tubeless tire as a substitute for a proper repair.
If the tire has a puncture in the tread which exceeds 1/4-inch (6mm), any puncture in the sidewall, or if more than one radial cable per casing ply is damaged, the tire must be removed from service and replaced.
Speed Ratings. When a Cooper-produced speed rated tire has been repaired, the speed rating no longer applies.
The speed capability of the vehicle is limited by the speed capability of the repaired tire. When a Cooper-produced speed rated passenger tire has been repaired, the tire's maximum speed is 85 mph (137 km/h).
Storing Tires
Use care when storing tires.
When tires are stored they should be stored in a cool, dry place away from sources of sunlight, heat and ozone such as hot pipes and electric motors. Tires should be stored so there is no danger of water collecting inside them. Be sure that surfaces on which tires are stored are clean and free from grease, gasoline or other substances which could deteriorate the rubber. Tires exposed to these materials during storage or driving may be weakened and subject to sudden failure. Also, be sure to allow air to circulate around all sides of the tires, including underneath, to prevent moisture damage.
When storing tires flat (one on top of the other), stack so that tires on the bottom retain their shape.
If storing tires outdoors, protect them with an opaque waterproof covering and elevate them from the ground. Do not store tires on black asphalt, other heat-absorbent surfaces, snow-covered ground or sand.