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boxrodz · 04-09-2005, 07:47 PM

Not quite.

In your example, 235 refers to the width of the tire (in millimeters) at its' widest point and not the height. The 85 refers to the ratio of the height with respect to the width. A 85 series tire is considered to have a very tall sidewall. I think the stock tires are 225/75/15 which are 28.29" tall (225*75*(2/2540)+15). To give you some flavor:
A 255/60/15 tire is 27.05" tall.
A 275/60/15 tire is 28" tall.
A 245/70/15 tire is 28.5" tall.
A 255/70/15 tire is 29.06" tall.
The 60 series tires are more popular than the sometimes uncommon 70 series tires.

Visit the tirerack to see what tires are available for the size tire you want to run. It'll also give you the tire specs (dimensions) and the recommended rim width for a given tire.

What kind of look are you after? Do you want to stick with the same size tires at all four corners? Are you planning on lowering (or raising) your truck in the future?

04-09-2005, 07:47 PM	#3
boxrodz Until Seventy Times Seven Join Date: Feb 2005 Location: Rocky Mountain Front Range Posts: 1,301	Not quite. In your example, 235 refers to the width of the tire (in millimeters) at its' widest point and not the height. The 85 refers to the ratio of the height with respect to the width. A 85 series tire is considered to have a very tall sidewall. I think the stock tires are 225/75/15 which are 28.29" tall (22575(2/2540)+15). To give you some flavor: A 255/60/15 tire is 27.05" tall. A 275/60/15 tire is 28" tall. A 245/70/15 tire is 28.5" tall. A 255/70/15 tire is 29.06" tall. The 60 series tires are more popular than the sometimes uncommon 70 series tires. Visit the tirerack to see what tires are available for the size tire you want to run. It'll also give you the tire specs (dimensions) and the recommended rim width for a given tire. What kind of look are you after? Do you want to stick with the same size tires at all four corners? Are you planning on lowering (or raising) your truck in the future? __________________ boxRODz 1983 C10 SWB Fleetside When two halves is gone, there's nuthin left. Two nothings is nuthin. That's mathematics son. You can argue with me but you can't argue with figures. Two half nothings is a whole nuthin... Last edited by boxrodz; 04-09-2005 at 08:31 PM.