What do tire measurements mean?
Glad you asked...
The measurements on a tire stand for the tires aspect ratio, wheel diameter as well as the width. It is read Width /wheel diameter and aspect ratio. The letters in the dimension can stand for Radial and VR.
lacharron, Shopping Expert
Then again, this answer might help you...
Tire measurements mean a few different things. First we will look at a certain tire size, such as P235/75R15...the size of our truck tires. The P means P-metric, or referring to passenger vehicles. The next number means the measurement in millimeters of the tire from the outer sidewall to the inner sidewall when it is mounted on a rim. The 75 in this case refers to the sidewall height from the rim to the tread. The R means it is a tire made by radial construction, and the 15 means rim size diameter in inches.
brsmom68, Shopping Expert