Tire Designations

Tire Size

The following is an example of a typical passenger vehicle tire size.

(A) Passenger (PMetric) Tire:

(A) Passenger (PMetric) Tire:

The United States version of a metric tire sizing system.

The letter P as the first character in the tire size means a passenger vehicle tire engineered to standards set by the U.S. Tire and Rim Association.

(B) Tire Width: The threedigit number indicates the tire section width in millimeters from sidewall to sidewall.

(C) Aspect Ratio: A twodigit number that indicates the tire heighttowidth measurements.

For example, if the tire size aspect ratio is 60, as shown in item C of the illustration, it would mean that the tire's sidewall is 60 percent as high as it is wide.

(D) Construction Code:

A letter code is used to indicate the type of ply construction in the tire. The letter R means radial ply construction; the letter D means diagonal or bias ply construction; and the letter B means beltedbias ply construction.

(E) Rim Diameter: Diameter of the wheel in inches.

(F) Service Description: These characters represent the load index and speed rating of the tire. The load index represents the load carrying capacity a tire is certified to carry. The speed rating is the maximum speed a tire is certified to carry a load.

    See also:

    Keyless Locking
    If the vehicle has the keyless access system, this feature allows you to select whether the doors automatically lock during normal vehicle exit. When the vehicle is turned off and all doors become c ...

    Transferring Service
    Push to request account transfer eligibility information. The Advisor can assist in canceling or removing account information. If OnStar receives information that vehicle ownership has ch ...

    Customer Satisfaction Procedure (Mexico)
    Did you get the Warranty Extension Plan? This plan is recommended by General Motors to supplement the warranty included with the new vehicle purchase. See your dealer for details. Customer Assis ...