jeep07

I just got my M/T tires LT285/75/R16. When i lat tire flat and use level, it only measures 10" . On the chart the tire is supposed to be 11.50 wide. Question, after the tire is mounted on rim and air is put in, will the width increase??? Thanks

armycop

Most tires are measured with air, mounted and on a certain rim width. The more narrow the rim, the more "bulge" you will get. The measurements are not exact, and with some tires, you will be closer to 11" than 11.5". It depends on the manufacturer. I had Bridgestone Revos that were wider than my Big O tires of the same exact size.

easttnruby

An inch or more difference is a bit much, but realistically most tires dont measure out to there sidewall reading. Most are usually a little larger or smaller but rarely dead on.

JK-KJ

also, the 11.50 you're referring to is section width not tread width...tread width should be a little more narrow.

Dante

Everyone it correct here. I have a 255/85R16. This is 33x10, but my tread width is only 7".

TEEJ

Yes, when you inflate the tire, it gets larger.



Same for the diameter and tread width, etc...albeit radials' diameter changes very little when inflated.

If you inflate it to mount psi....and remeasure it sidewall to sidewall, it should be ABOUT 285 mm or 11.5"...these are nominal sizes, so, a 1/2" or so either way is not too unusual, etc....or important.

I'm MUCH more interested in tread width than sidewall size...IE: I want MORE tread width...the sidewalls just get caught on more stuff if fatter than need be, etc.

For example, on the BFG AT ko....the 33 x 12.5/15 tire is a little shorter, and has a little less tread width, than the same tire in a 305/70/16, which is technically a 33 x 12.0/16 tire....but the 33 x 12.5/15's SIDEWALL is fatter....more sidewall, less tread in that case....not a great trade, etc...

So - inflate it, re-measure. Then, put it on the jeep...and measure again...as it will change again with the load on it, getting shorter and fatter.