ok im im sitting here lookin at my tires right...i have some 18's and some 17's my 18's tire size is 215/35/18 my 17's is 215/45/18 both look like the same identical width...my 17's have a taller tire itself...so what im asking is...what do the #'s represent...215 is width right? what is the 35 or 45?

215 is width in millimeters. 35 and 45 are how tall the sidewall is in millimeters. And obviously 17 and 18 are the rim size. They are the same width.

The second number is a percentage, meaning in this case a 215/35/18 is 215 mm wide on a 18 inch rim and the side wall is 35% of the width.

http://www.tirerack.com/tires/tiretech/general/size_information.jsp

I stand corrected. Thanks.;)

yeah a lot of people make that misconception.. in reality, a 35mm sidewall would be ridiculous.. pull out a ruler and see how big your sidewalls are compared to 35mm.. they're actually probably around 70-80mm.. its not a uniform variable..

Makes sense. Its just one of those things that I didn't put into perspective.

yea that was what i was having a problem with was the second # really...i was looking and im like ok there 215 mm wide...but def not 35 or 45 mm high...was confusing me...thank everyone for solving my mystery...hope it helped some other people to..

thats the number where like, if its 40, people will call the tires "40 series" right? i know i have heard that before but i have never heard someone say that and then hda the chance to look to inspect what their tire says...

Yeah, it's weird, tires are like the only thing that uses 3 different types of measurements, millimeters for width, inches for diameter and percentage for thickness.

Standard measurements can die.

I say metric all the way.

metric rulllllzzzz.....

i must say that with the 215mm...wouldnt it just be easier to say like 8in...so much more simple i think...then again 215 is alot more accurate...

i must say that with the 215mm...wouldnt it just be easier to say like 8in...so much more simple i think...then again 215 is alot more accurate...


Not that the accuracy is needed since every 215 tire is a different width...

uummm....215 tires are all....uuhhh...215mm wide.

I would say 21.5 cm. Or 2.1 decimeters. Thats the beauty of the metric system. It is so easy to convert to another measurement. Just move the decimal one way or the other.

damn that math class.