I have a 35-12.50-17 on my truck now. My question is....What does that exual out to? A 315-70-17? The reason I am asking is because I am trying to see the difference between to tires I have now and the factory oem 20's. I am using discounttire.com's tire calculator to figure this out.

 

The factory 20's are 31.9 inches tall and around 11 inches wide. Are you thinking of getting a pair?

Nebraska

 

Yes I already have a set on the way. I know what the dim's are on the 20's I need to know about the 35's I have on there now. The website will not take the 35-12.50-17 It has to be a 305 or a 315 number. I know there is a very close comparison but I am unsure what it is.

 

315 70R 17 is equivalent to a 35 12.50 17 but it measures about 34.6 inches if my memory is correct.

 

I don't have a clean conversion for you but a 315/70R17 is 34.36" x 12.40" and a 315/75R17 comes out to 35.6" x 12.40"

The math is

Tread Width: (1st#)315 Divide By 25.4 =12.40

Then multiply that # by the aspect ratio (2nd# in the tire size), in this case 75 % and you get 9.30. Multiply this # X 2 and add whatever your rim diameter is and it gives you the overall height.

9.30x2=18.60+17=35.60" overall.

I don't think a 35 x 12.50 has a straight metric size conversion. Feel free to play around though.

 

Right, a 315/70-17 is essentially a 35x12.50-17. Remember, tire sizes are usually rounded up to the next whole number. Most all "35's" are in the 34 1/2 to 34 3/4 inch range.