When it's time to replace tires, there are a number of factors to consider. By upgrading to a different or more sophisticated type of tire, you may be able to noticeably improve the performance of your vehicle in terms of the way it handles under certain conditions. Additionally, there are a number of variables -- including road conditions and driver habits -- that will impact on the performance and useful longevity of the tires you use. Your choice of tires should take into consideration whether you do any of the following: - Do mostly highway driving
- Drive mostly in city traffic with frequent stops and starts
- Drive frequently on unpaved or rough road surfaces
- Carry heavy loads in your vehicle
- Are an "aggressive driver" who is hard on tires -- such as by accelerating through turns
- Live in an area of the country that frequently has rain, ice or snow.
Specific styles and constructions of tires are designed to function best under specific conditions. It's important to select a tire that is suited for the driving conditions to which it will be exposed. A reputable tire specialist can assist you in matching a tire to the type of driving you'll be doing. Nevertheless, it's wise to be somewhat educated about the common types of tires that are available. All-season tires are the basic, generalist tire. They are the standard on most new vehicles and are suitable tires for average driving. The tread on the all-season tire (figure A) is designed to provide good traction year round -- during wet or snowy seasons as well as warm, dry ones. They are also designed to provide a smooth, quiet ride. A designation of "M+S" embossed on the sidewall indicates that the tire is designed to perform well in inclement weather when there is likely to be mud and snow. Wet-weather tires are basically an all-season design with an added benefit. The tread on these tires (figure B) incorporates center-channels that, in rainy conditions, helps dissipate water by channeling it toward the outside of the tire. This design allows the tire to maintain good traction when there is water on the road and helps prevent loss of control through hydroplaning. All-terrain and off-road tires are designed for four-wheel-drive vehicles and SUVs. If you're more interested in off-road adventure than you are a smooth, quiet ride, then off-road tires (figure C, right ) may be the tires you're looking for. All-terrain tires (figure C, left ) are also designed to withstand rugged, off-road conditions, but they compromise somewhat with a slightly smaller, less aggressive tread design. Neither of these styles of tires is very well suited for highway driving. Because of their large, coarse tread, they are noisy on the road and will lower your vehicle's gas-mileage efficiency. They also wear out quickly when driven frequently on pavement. They are, however, designed to meet such challenges as charging ahead through muddy terrain or climbing over slick rocks. Performance tires are built to perform well when pushed toward the limits in terms of speed, acceleration, braking and cornering. This type of tire is preferred on sports cars and by driving enthusiasts who tend to drive more aggressively. They generally have a high-speed rating and structurally are wider and lower in profile. They are generally noisier than all-season tires and provide a less comfortable ride. Some feature asymmetrical tread design (figure D), and some even have colored treads for a sporty look. With asymmetrically designed tires, it's critical to make certain that the tire is mounted with the correct side facing outward as this will have an impact on handling. There is also a category known as ultra-high performance tires that offer the maximum in terms of driving performance but wear out even more quickly than regular-performance tires. The dominant features of all performance tires are greater width and a sophisticated tread design (figure E) that provides improved grip on the road surface. Since they use a softer tread for better road stability, they tend to wear out quickly. Self-sealing tires are essentially punctureproof because they have a rubbery, gumlike lining that allows the tire to "self-seal" in the event that it is punctured by a nail or other sharp object. In the event of a minor puncture, the gummy substance fills the hole from the inside before the tire has a chance to go flat. These tires are designed to give peace of mind to drivers who don't want to get caught changing a tire in a dangerous roadside setting. More tips for purchasing tires - Never mix and match different tire constructions on the same vehicle. Various construction styles are made to impact driving performance in specific ways. Always replace a radial tire with radial tire -- not with a bias-belted or bias-ply. Mixing dissimilar tires on the same vehicle will negatively impact alignment and performance and may be dangerous. If your vehicle has bias tires that are worn out and you intend to upgrade to radials, it will be necessary to replace all four tires with radials at the same time.
- Never use two different sizes of tire on the same axle.
- If replacing just one or two tires, put the newer tires on the front of the vehicle for better control when cornering and braking.
- The ideal situation is to replace all four tires at the same time, or at least replace two on the same axle at the same time. Having a single oddball new tire on the same vehicle with three worn tires may negatively impact ride and alignment.
- The proper tire size for your vehicle is listed in your owner's manual and may also be printed on a decal attached to your vehicle -- usually on the door edge or in the trunk.
RESOURCES :
Auto Repair for Dummies
Author: Deanna Sclar
ISBN: 0764550896
Tires, Suspension and Handling
ISBN: 1560918314
Author: John C. Dixon
(Society of Automotive Engineers
| 
)
)
)
)
)
)
)
