need tire sizes explained

[smokin'Red35th]

Can someone please explain tire sizes to me?
245/45/17 - what does each # mean. I know 17 is for a 17" wheel, but i have always been confused about the other two numbers.
Thanks in advance

 

[ProCharger GT]

245 = width of the tire in mm
45 = aspect ratio = the height of the sidewall is 45% the width of the tire

 

[smokin'Red35th]

THANK YOU!
Now whats the widest tire i can fit on a stock 17" rim?

 

[MY Cobra]

i have 275/40/17's on mine now. Dunno if that helps any.

 

[ProCharger GT]

275/40/17 for the rear and 255/45/17 for the front. i chose to run the standard 245/45/17 on my front though; i know of someone who has the 255's and they fit, but i dont know if there is any turning/rubbing issues.

 

[tangerine]

I am glad that you all know that the 245 is the width because I had 2 shadetree mechanics argue me up and down that it was the height not the width.

 

[chevylover]

275's all the way

I run what I have in my sig and have had no problems. You'll have some people tell you that 275's on the stock 17x8 rim is to wide and some online dealers give min. rim width for a 275 as 9 inches. They look good on my 17x8's and I would recommend them. But that's only because I stayed at a Holiday Inn Express last night!!

 

[smokin'Red35th]

thanks guys. i appreciate it!

 

[02camarokiller]

I run what I have in my sig and have had no problems. You'll have some people tell you that 275's on the stock 17x8 rim is to wide and some online dealers give min. rim width for a 275 as 9 inches. They look good on my 17x8's and I would recommend them. But that's only because I stayed at a Holiday Inn Express last night!!

 

[Mega-Man]

245 / 45 / ZR17 all-around here...

 

[Black 2001 GT]

255/40/17 all around here