How To Measure A Tire For A Spare Tire Cover

Updated 06/10/2015 | Published 06/08/2015

Products Featured in This Question

Classic Accessories RV Tire Covers for 24" to 27" Tires - Single Axle - White - Qty 2

(749)

$46.25

Classic Accessories Spare Tire Cover for 26-1/2" to 27-1/2" Diameter Tires - White - Qty 1

(508)

$31.09

Question:

How do I measure the tire to find out what size cover I need your list does not give my tire size

asked by: John

Expert Reply:

To find the size of your tire, the easiest way is to just measure the distance from the ground to the top of the tire.

I have attached a couple help articles that explain tire sizing. The first 3 numbers are the Section Width. For example, if the number is 175 it means 175 millimeters wide. If it is listed as 4.80 that means the tire is 4.80 inches wide.

The two digits following the Section Width is the Aspect Ratio. If that number is 80 you would take 80 percent of the Section Width. On a tire that is ST175/80-R16, you would take 80 percent of the 175, which would be 140 millimeters. To convert to inches multiply 140 x .0394. The section height would be 5.526 inches.

The last 2 numbers is the diameter of the wheel the tire would be mounted on. If it is 16, then the wheel is 16 inches diameter.

So, for a tire that is labeled ST175/80-R16, you would multiply the Aspect Ratio of 5.526 x 2, which would be 11.052. Add that to the 16 inch wheel diameter and your height would be 27.052. for a tire this size you could use a cover like part # 052963751307, which fits tires from 26-1/2 to 27-1/2 inches.

expert reply by: Jeffrey L