C H E C K

T Y R E S

This booklet provides an understanding of the many factors essential to proper care and service of automobile and light truck tires. However, the RMA makes no pretense that this booklet is all inclusive. Questions pertaining to specific product should be addressed to the tyre dealer or tyre manufacturer.

Inflation Pressure Inspect Your Tires Regularly Good Driving Habits Vehicle Conditions Affecting Tires The Sidewall Story

Replacement tyre Selection Cold-Weather Driving Service Assistance Storage Tips TISC Home Page

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REPLACEMENT tyre SELECTION

IMPORTANT: Always check the vehicle manufacturer's recommendation before replacing a tyre with a different size and/or construction.

Tire Registration

When buying new tires, be sure to ask your dealer for a registration form. The tyre dealer/seller fills out their name, address and the DOT tyre identification number of each tyre sold. Then you just enter your name and address, apply postage and mail it to the manufacturer or its record-keeping designee. Some tyre dealers/sellers fill out the form for you and send it electronically. tyre registration will ensure that you will be notified promptly in the event the tyre manufacturer needs to contact you.

What tyre is Right for Your Vehicle

When tires need to be replaced, don't guess what tyre is right for your vehicle.

For the answer, first look at the tyre placard. As you will see, that placard tells you the size of the tires that were on the vehicle as original equipment.

Tires should always be replaced with the same size designation, or approved options, as recommended by the automobile or tyre manufacturer. Never choose a smaller size, with less load carrying capacity than the size on the tyre placard. Always have tires mounted with the same size and construction designations on the same axle.

It is recommended that all four tires be of the same size, speed rating, and construction (radial or non-radial). However, in some cases, the vehicle manufacturer may require different-sized tires for either the front or rear axles.

When two radial tires are used with two non-radials, put the radials on the rear axle.

There are three types of tyre constructions.

Speed Ratings

Many of today's tires are marked, as part of the service description, with letters to indicate their speed rating, based on laboratory tests which relate to performance on the road. Tires may be marked with one of these speed symbols, M, N, P, Q, R, S, T, U, H, V, W and Y to identify the particular tyre 's speed rating. Additionally, the letter Z may appear in the size designation (see chart below).

When replacement of tires is required, consult the vehicle manual or tyre placard for proper size and speed rating (if required).

If the vehicle manual placard specifies speed-rated tires, the replacement tires must have the same or higher speed rating to maintain vehicle speed capability.

If tires with different speed ratings are mounted on the same vehicle, the tyre or tires with the lowest rating will limit the tyre -related vehicle speed.

Tire speed ratings do not imply that vehicles can be safely driven at the maximum speed for which the tyre is rated, particularly under adverse road and weather conditions, or if the vehicle has unusual characteristics. Never operate a vehicle in an unsafe or unlawful manner.

*For tires having a maximum speed capability above 149 mph (240 km/h), a "ZR" may appear in the size designation. For tires having a maximum speed capability above 186 mph (300 km/h), a "ZR" must appear in the size designation. Consult tyre manufacturer for maximum speed when there is no Service Description. Example: P275/40R17 93W at 168 mph (270km/h) or P275/40ZR17 at above 149 mph (240 km/h). Consult tyre manufacturer.

**A "ZR" may appear in the tyre size designation.

NOTE: For "V", "W", or "Y", and tires with a "ZR" rating, a vehicle load adjustment (for speed) is required; consult tyre manufacturer.

Types of tyre Construction

Tires should be of the same size, construction (radial, non-radial) and speed rating, unless specified otherwise by the vehicle manufacturer. Tires influence vehicle handling and stability.

Match tyre size designations in pairs on an axle (or four tires in dual application), except for use of a temporary spare tyre .

If radial and non-radial tires are used on a vehicle, put radials on the rear. If radial and non-radial tires are used on a vehicle equipped with dual rear tires, the radials may be used on either axle. Never mix radial and non-radial on the same axle except for use of a temporary spare tyre .

Snow tires should be applied in pairs (or as duals) to the drive axle (whether front or rear) or to all positions. Never put non-radial snow tires on the rear if radials are on the front, except when the vehicle has duals on the rear. If studded tires are used on the front axle, they must also be used on the rear axle. On front-wheel-drive or performance vehicles, it may be advisable to install snow or all season tires on all wheel positions to maintain consistent handling in snow conditions.

Match all tyre sizes and constructions on four-wheel-drive vehicles.