P= For Passenger Cars, SUVs, MiniVans & Light Trucks. LT = Heavy Load Trucks, Vans or SUVs. There may not always be a letter on your tire size. To simply searching for tires. Our tire search database will not show this.
The 185 indicates this tire is 185 millimeters across from the widest point of its outer sidewall to the widest point of its inner sidewall when mounted and measured on a specified width wheel.
Refers to the height of the sidewall. It is a percentage of the section width. In our example, 65% percent of the section width of 185mm.
The "R" in our example indicates this is a radial tire construction. 98% of tires have an "R" construction.
In our example, the diameter (the hole where your rim sits) is 15 inches across.
The load index is how much weight the tire can support. Most vehicles come with a recommended tire load index. SAFETY ALERT: It is NOT recommended that you use a lower load index. You CAN use a higher load index.
The letter refers to the maximum speed the tire should travel. However, also realize the speed rating is not just speed. It is also performance and handling. SAFETY ALERT: You should not "downgrade" the speed rating and all four tires should have the same speed rating.
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