Recent research by the National Highway Traffic Safety Administration (NHTSA) indicates about 30% of cars and light trucks have at least one tire underinflated by 8 psi or more. Underinflated tires and overloaded vehicles are the leading cause of tire failure. It is extremely difficult to tell just by looking at your tires if they are properly inflated.
Purchase an accurate tire gauge and check your tire pressures at least once a month along with their overall condition. Take note of tire pressures and load limits.
Making sure that your vehicle is operating with properly inflated tires will make you safer on the highways and increase fuel savings.
When To Check Tire Pressure
Check inflation pressure, including the spare, at least once a month and before every long road trip. Tires must be checked when they are cold which means you have driven less than one mile on them. If you must drive over a mile for air, measure and record the under-inflation amount of each tire. Upon arriving at the service station, measure each tire's inflation again and if the pressure has increased, adjust the amount of additional air pressure needed. For example, if cold pressure should be 35 PSI, but cold pressure was 28 PSI, and current pressure is 33 PSI, you should inflate the warm tires to 40 PSI and recheck them again when cold.
How Do Tires Lose Pressure?
Tires lose pressure naturally through the process of permeation or, air passing through the pores of the tire. Changes in outdoor temperature can affect the rate at which tires lose air. This change is more pronounced in hot weather. Generally speaking, a tire will lose one or two pounds of air pressure per month in cool weather and even more in hot weather. Remember, underinflation is the leading cause of tire failure, so check inflation pressure regularly.
- Never "bleed" or reduce air pressure when tires are hot. It is normal for pressures to build up as a result of driving.
- Make sure all tire valves and extensions are equipped with valve caps with rubber gaskets to keep out dirt and moisture. Have a new valve stem assembly installed whenever a tire is replaced.
Using Your Spare
Most vehicles come equipped with a temporary spare. These tires are usually much smaller than the other tires on your car. It is important to realize that these spares have far more limitations than a typical tire, including speed and recommended driving distance. Some spare tires even require the use of a special canister to inflate the tire.
You should familiarize yourself with the spare by reading the owner's manual and the sidewall of the spare. And remember to check the air pressure of your spare frequently.
The purpose of regularly rotating tires is to achieve more uniform wear for all tires on a vehicle. Your vehicle's owner's manual will likely have rotation recommendations. If no rotation period or pattern is specified, you should consider rotating your tires, front to back, every 6,000 miles or at least every 7,500 miles. Irregular wear may require more frequent rotation.
After rotation, adjust individual tire air pressures. See the proper inflation section for details.
Popular Rotation Patterns
The following are popular rotation patters. However, some tires cannot be rotated according to popular patterns. Such tires include uni-directional tires with asymmetric tread designs. Also, some vehicles may have different sized tires mounted on the front and rear axles, and these different sized tires may also have rotation restrictions. Check your owner's manual or visit your Toyo tire dealer for recommendations for these special cases.
You may have noticed small weights placed on the rim of your tire. These weights help the tire and wheel assembly remain balanced at all speeds. At high speeds a tire that is not balanced properly can generate severe vibrations. An unbalanced tire and wheel can also lead to irregular treadwear.
Some expensive alloy wheels can be damaged with the use of standard lead weights and may require the use of a coated weight.
Proper alignment is essential for optimum performance and maximum tire life.
Misalignment in the front or rear, improperly operating brakes or shock absorbers, bent wheels, worn bushings, and any other mechanical problems can cause uneven and rapid treadwear.
It is also important to note that front-wheel-drive vehicles and those with independent rear suspensions require special attention, and alignment should be checked periodically.
And finally, a bad jolt - such as hitting a pothole - can throw your vehicle out of alignment. Such an impact can also bend the rim, causing a loss of air pressure and damage to your tires with little or no visible evidence present. If this happens, see your Toyo Tires dealer for a tire inspection.
At least once a month, inspect your tires closely for signs of tire damage such as cuts or punctures as well as uneven or excessive wear.
When inspecting your tires, you should also look for any stones, bits of glass, metal, or other foreign objects in the tread or sidewall. These may work deeper into the tire and cause air loss. Damage to the tire, wheel, or valve may be the problem.
Tire Damage - Repair or Replace?
Which types of tire injuries are serviceable? The answer to that question depends upon the injury itself.
Air loss due to punctures can ruin tires that might have been saved had they been removed in time for proper repair. Gradual air loss causes a tire's operating temperature to rise, which can cause some components to separate, or damage the tire body in ways that create rapid, or sudden air loss.
To be safe, a Toyo Tires dealer should evaluate every injury, including punctures, scrapes, bulges, separations, or cuts.
When the tread is worn down to 2/32nds, or one-sixteenth of an inch, the tire is worn out and it is time to replace it. Built-in treadwear indicators, or "wear bars," which look like narrow strips of smooth rubber across the tread, will appear on the tire when that point of wear is reached.
Improper inflation pressures, misalignment, improper balance, or suspension neglect may cause uneven wear patterns. If not corrected, further tire damage will occur. If you discover uneven wear, take your car to your nearest Toyo Tires dealer. In many instances, the dealer can correct the problem so you can continue to use your tires.