Maintaining proper air pressure is the single most important thing drivers can do for their tyres. In the space of just one month, a tyre can lose two pounds of air pressure.
It is important to check the air pressure of your tyres regularly to make sure your tyres are neither under- nor overinflated.
Underinflation is the worst enemy your tyre can have. It causes increased treadwear on the outside edges (or shoulders) of the tyre. It also generates excessive heat, which can reduce tyre life. Finally, it reduces your fuel economy by increasing rolling resistance — soft tyres make your vehicle work harder.
Overinflation is also detrimental to the tyre. Too much air pressure causes the center of the tread to bear the majority of the car's weight, which leads to faster deterioration and uneven wear. Any kind of uneven wear will shorten the lifespan of your tyres.
To find the proper air pressure for your tyres, look in the vehicle owner's manual, on the sticker on the driver's side doorjamb or in the glove box. If you buy new tyres, be sure to learn the correct pressure from your tyre Retailer or the owner's manual of your vehicle. Check your pressure at least once a month, and use a high-quality air gauge.
Balance and Alignment
Having your tyres balanced and your vehicle properly aligned is important not only to the longevity of the tyre but also to the safety of the driver and to the performance of the car.
Unbalanced tyres cause road vibration, which can lead to driver fatigue, premature tyre wear (also known as cupping or dipping) and unnecessary wear to your vehicle's suspension. Tyres should be balanced when they are mounted on wheels for the first time or when they are remounted after a repair. They should be rebalanced at the first sign of a vibration or shimmy and should be balanced at least once a year, regardless.
A vehicle is said to be properly aligned when all suspension and steering components are sound and when tyre and wheel assemblies are running straight and true. Proper alignment is necessary for even treadwear and precise steering. Uneven front or rear tyre wear, or changes in your vehicle's handling or steering, can indicate misalignment.
The cost of keeping your tyres balanced and your vehicle properly aligned will more than pay for itself in tire mileage, performance and comfort.
The weight of a vehicle is not evenly distributed to all four tyres. Therefore, regular rotation is necessary to maintain even treadwear and get the most out of your tyres.
There are several methods of rotation. For all-season tyres and most vehicles on the road, tyres from the rear axle are moved to the drive axle and crossed to opposite sides of the vehicle. The tyres from the drive axle are moved to the rear but remain on the same sides. This is known as the "modified X" pattern.
Tyres with "directional" design are rotated differently. In this case, all tyres remain on the same side of the vehicle and are rotated straight forward and straight back. For four-wheel-drive vehicles, it is recommended to switch all four tyres, both from side-to-side and in axle position.
Check your vehicle owner's manual for the manufacturer's rotation recommendations. If no rotation period is specified, tyres should be adjusted every 6,000 to 8,000 miles. Four-wheel-drive vehicles may require rotation more often. The first rotation of your tyres is the most important, and remember to adjust inflation pressures to the vehicle manufacturer's recommendations after every rotation.
Giving your tyres a good visual once-over can help you discover punctures or other visible signs of damage that may make replacement necessary. The next time you check the air pressure of your tyres, scan the treads for any sharp objects that may have punctured your tyres. Even if the puncture is not deep enough to flatten the tyre immediately, the cracking and pitting caused by smaller punctures can eventually worsen and lead to problems down the road.
Check the wear patterns on your treads as well. Excessive shoulder wear can indicate underinflation, while wear to the center of the tread can mean overinflation.
Many tyres have treadwear indicator bars molded into the tread. When the tread is worn down to where you can see a solid bar of rubber across the width of the tread, it is time to replace your tyre.
It is crucial to know when it is okay to have a tyre repaired and when a tyre should be replaced. If a tyre loses its air pressure, it must be removed from the wheel for a complete internal inspection to be sure it is not damaged. Tyres that are run even a short distance while flat are often damaged beyond repair.
Most punctures, nail holes or cuts up to 1/4 inch can be repaired by trained technicians as long as the damage is confined to the tread. DO NOT repair any sidewall puncture or tyres with tread punctures larger than 1/4 inch. Also, never repair tyres which are worn below 1/16 inch of tread depth. Most tyre repairs should be handled by trained professionals. Be sure that your spare tyre is inflated to the proper pressure and properly maintained.