Ok I've searched and seen a ton of 285,305/70/17's but have yet to see any with 315's so roughly 34.4" I know that 285's are 33" and 305's are just under 34..I've got the kit in and have the rims Pintlers and have decided that Duratracs are the tire but know just size..285's and be safe or go 315's and be a bit tight..Jeep will see trails and hunting ..no rock crawling to extreme and it's a 2010 rubi unlimited duel top and tow ..any pics or thoughts? I measured and I know I have room but would be nice to see if anyone has tried and thier opinion.

 

actually a 28570r17 measures to be a narrow 33. With the right offset a 305 would look and work better. I have 315's on mine with a 4 inch lift. It does great with no rubbing. Look out though. different tire manufacturers tires measure different from eachother regardless of the number. I know from experience.

 

I may be misreading what you are saying, but my understanding of tires is that 315s are wider (not taller)? Your height will come from the second number 70, 75, etc.

 

For the most part that is correct. But the first number can also attribute to the height.

For example 305/70/17 is 33.9" while 315/70/17 is 34.4", both on a 10" rim. Here is a neat site to compare tire sizes: h t t p://www.wheelsmaster.com/rt_specs.jsp

Also what CJ THAT WENT JK says is true, the above is an estimated size, each manufacturer's overall size can vary.

 

it should be fine im running 315s with a 2.5 bb

 

Sorry I should have been clearer the tires i'm looking at are

• LT285/70R17 at 32.8" on a 8.5" rim and 11.5" wide

• LT315/70R17 at 34.4" on a 9.5" rim and 12.7" wide

my rims are 8.5" and have the offset and only a 1.6" diff in hieght
so anyone have 315 duratrac's that they can measure??