turbojimmy

I know there are hundreds of posts (maybe thousands) on rim/tire combos but I'm having a hard time sorting through it all.

My stepson has an '08 Wrangler Rubicon. His dad got him a set of rims as a gift about a year ago. We were waiting for his tires to wear out before we put them on. Well here we are....

It currently has the stock rims on it with 255/70 tires. I understand that these are a bit shorter than the stock 255/75s. The rims his dad got are 17x8.5 with 5.5" backspace and +19mm offset. I have no idea if this is a good combo for it. The backspacing seems to be a fairly common option on a 8.5" rim. Not sure about the positive 19mm offset. Looking at the invoice, looks like he got them from Tire Rack for an '08 Wrangler but Tire Rack no longer sells these particular rims.

So I guess long story short is I'm going to put some all-season light truck tires on it. Would the stock sized 255-75-17s be okay or should I go to a 285-70? I don't want to upset the handling characteristics of it much and it needs to do well in the snow (packed snow, icy roads - not offroad).

Advice would be greatly appreciated.....

nthinuf

Stock rims have around a 6.25" backspace. As that number goes down, the rims/tires move further out of the wheel wells. So swapping the current tires to those new rims, they would move out about .75" (maybe a bit more since the new rims are wider?). Then you look at any difference in width of the old tires to the new tires, and you will get an idea of just how far out they will sit.

Offset uses the specific rim width in the calculation for how far in or out of the wheel wells the rims sit, so it's a bit more confusing to use. But higher/positive is further in, lower/negative is further out. How far will vary with the specific width of the rim.

Anyway, with a 5.5" backspace, you are perfectly fine with stock size tires, and should be good up to a 33x12.50 or so. Some folks are running 35x12.50's on them, but generally with a lift and/or fender mods and/or steer stop modification.

cjnomo

I'd stick with 10" wide tires. I have 12.5" tires right now on wheels with 4.5" of backspacing, and I rub on my frame and sway bar up front.

turbojimmy

Thanks both for the replies. I'm going to order up the stock-size tires today.

resharp001

Really? I ran 35x12.5 with a 4.5" backspacing and never rubbed. I now run 37x12.5 on the same wheel and only had to add 2 washerss to my steering stop to keep from rubbing on the frame.

cjnomo

Fair disclosure. I'm running with no lift. I'm sure when I finally get around to installing my 3.5 Game Changer lift (it's sitting in my garage right now).... that will take care of that.

turbojimmy

I should have mentioned that the Rubicon is bone-stock. Not sure why his dad got him aftermarket wheels for it (tires would have been better), but I suppose it was a nice gesture. The invoice says "Aggressive fitment. Vehicle should have lift kit or fender modifications for proper clearance." In test fitting the rim on the back, it looked to me like even the stock-sized tire was going to be tight (which is why I posted here). I'm hoping I don't need to do anything but bolt these things on! They're mounting tires on the rims tomorrow - 255/75s.

cjnomo

Cooool!!! And one neat feature for future reference. Adding 1.5" wheel spacers with those 5.5 aftermarket wheels will give him 4.0 BS. So he will be set up next time around to run spacers and a set of 35 or 37x12.5s or maybe even 13.5s down the road.

cjnomo

Addressing ur OP question about 255 vs 285. A 285/70 should fit great. It's not the height of the tire that rubs on my jeep, it's my tire width/BS. So u could technically go 285 and that would be gtg. Post pics after the install!!!

marst23

I was on the fence with a similar situation and ended up just getting aftermarket wheels form DT. Now running 285 75 17s on MB TKO's no lift and no problems. I will be adding a 3 inch lift in the near future so I can upgrade to 35s.