jacksonpt

OK, help me think this through...

I've currently got stock 15x7 alloys. I believel the backspacing is 4.25, but I don't know that for sure. I've currently got 32" Dueler ATs with a section width of 11.9" and a tread width of 8.9". They do clear the upper a-arm, but under comression, not by much. I'm hoping to get a chance to measure the clearance this weekend.

I want to fit 33" Firestone Destination MTs.

The 33s have a section width of 12.5" and a tread width of 9.9". I'm going to focus on the section width because that's where I'm concerned the rubbing will happen. The 33s are .6" wider than my current 32s, which means they will be .3" closer to the a-arm, right? So if I got a set of wheels that had .3" less backspacing (pushing the wheel away from the suspension), I shouldn't have any clearance issues at the a-arm, right? I'm probably going to see if I can get some steelies with 4.0" BS... that's .25" less than stock. That will leave me with .05" of section width to possibly rub. I don't think I'm going to get too worked up over .05".

Do I have all this organized right in my head? Am I missing something?

RTdawgs

well heres what im thinking...

32x11.50 on a 7" wheel is prob more like 32x10.50.

33x12.50 on an 8" wheel will be about 33x12.00.

so if my estimates are correct, your tires will be 1.5" wider, which is 0.75" per side of the wheel.

i think the stock backpsacing is 4.5 or a tad more.

i would look for some 3 5/8" - 4" backspaced wheels. try to find someone with 33s (Va Beach Josh, Bunny Dave (same width at least), Ace, couple others) and see which wheels theyre using.

dont count on my numbers being exact, but the basics are that your new tire wheel combo is going to be a lot wider than your current setup and your wheels need to be the proper backspacing to clear them. also, are you getting a body lift?

jacksonpt

According the the bridgestone/firestone site, my 32/11.5-15s are 11.9" wide, and 33/12.5-15s are 12.5" wide. Why do you say they are actually more like 11 and 12" wide (less than their measurement). I could see the 33 being wider than it's spec'd measurement because of the balloon effect, but narrower?

I talked to a few people running 33s... the problem is that most of them are running 285-16s, which are narrower than 33-15s so they didn't have the same issues with clearance at the a-arm. The only person I've found running 33-15s is Marc Z, and he's tough to get in touch with. I did talk to him once and he gave me some info about what he did. I'd like to avoid as much trimming/hammering as possible (he had to do some before his BL).

And yes, I am doing a body lift, otherwise I wouldn't clear in the back.

RTdawgs

email me and ill give you marc's email.

according to TireRack, the Destination MT has a section width of 12.50 when measured on a 10" wheel. when put on an 8" wheel, the tire will not be as wide.

according to TireRack, the Dueler AT has a section width of 11.9 when measured on a 9" wheel. when put on an 7" wheel, the tire will not be as wide.

making sense?

what size body lift? Roger Brown? what are you doing about sliders and TJM?

jacksonpt

Yea, I guess that kinda makes sense. Not real intuitive, but I can see how that would be the case.

Yes, I'm going with a RB body lift... haven't decided on 1" or 2" yet, but only as much as necessary to clear the 33s in the back. The sliders are staying where they are... they already rub on the body, so the 1" lift will give jsut enough clearance. I'll have to figure out something for the TJM. I can probably fab up some type of bracket or plate to get things worked out. When I installed it, I I think I remember seeing that there was a bit of adjustment possible with the stock plates.

RTdawgs

i plan on getting a 1" RB in the next couple weeks.

the TJM brackets have enough play to minimize the gap that would otherwise be there.