Have a question about tire size and wheel fitment. I think I half way understand it all but wanted to bounce it off a few others to see what you thought.

I have a 2002 f150 screw fx4 currently running 35x12.50x17 on 17x8 wheels 4 5/8 inch backspacing. Everything is fine with this setup. For a different set of wheels and tires I'm looking at 36x12.50x16.5 tires on american racing baja 16.5x9.75 wheels with 4 3/8 inch backspacing.

Fender clearance will be fine, I'm not worried about that part. However, given the backspacing and tire size do you think the extra 1/4 inch of backspacing and the 1.75 inch wider wheel will keep frame rub at full lock away? I'm also assuming the tires will stick out of the wheel well a little over 2 inches more than they currently do, due to extra backspacing and wheel width. Is this correct?

 

The extra width will eliminated the rubbing on the frame but push them outward enough to create rubbing on the front bumper's lower valance. I'd also strongly recommend that you do not go with a 16.5 inch wheel. Not only is the 16.5 inch wheel's bead design very poor, tire selection is very limited and getting worse with every passing day.
Also, how much lift do you have?

 

Thanks for the info, kind of what I was thinking but until I saw it in practice it's hard to be sure what's going to happen.

The 16.5 wheels are more for utility/off road use than daily driver stuff. I'm planning to keep the 17x8's running BFG AT radials for street and normal use. Which have performed great so far. Then use the 16.5 wheels on other tires I can tear up and not worry about.
I have access to several sets of 36'' bias ply goodyear wrangler r/t II's pulled off of military humvee's with 90% tread life in them. As well as some 37'' military radials. So really the only cost associated with them is wheels and mounting/balancing. I like the idea of mostly cost free play tires I can rough up at will.

I know the 16.5 bead isn't very good in situations where you need to air down. In the future I plan on running bead locker wheels for serious off road only purposes. I know a guy who can cut and recenter military humvee wheels to custom backspacing and bolt pattern requirements. They make nice double beadlock off road wheels with optional runflat inserts for air down situations but not daily driver stuff at all.

About the front valance rubbing, one of the reasons I'm not very concerned about fender rub is that the truck no longer has a stock bumper. A weld shop custom fabricated an all steel bumper/brush guard for the truck and it has quite a bit more clearance around the wheel well and tires than the stock setup did. Truck has a 6'' fabtech front with 6'' skyjacker leaf springs for the rear. (wasn't fond of leaf spring blocks)

 

Have another question about aftermarket wheels and lug nuts. Let's say for example new wheels don't happen to include lugs. The wheels call for a 60 degree conical seat lug, is it alright to use the stock lugs provided they fit in the channel correctly? I have the chrome jacketed lugs with the flat washer on the bottom that look like this:

 

I'm gonna guess by your post that you're looking at some of those Military surplus HMMVW tires? Goodyear Wrangler R/TIIs?

There are much better M/T tires available out there...The R/TII is a government-issue "compromise" tread pattern. They've got nice lugs on the side but have what pretty much amounts to a highway rib tread pattern up the middle. They just plain suck when it comes to mud & snow since they don't clean very well and are only so-so for rock crawling...I can't tell ya how they fare in sand though. About all they do is howl going down the road. Plus, they're bias-ply and their on-road handling leaves a lot to be desired.
Their surplus pricing pretty much reflects their performance.

I'd go with a more common rim size and look at some of the "civilian" M/T tires out there like the BFG M/T KM2, Toyo M/T, etc...you'll be much happier with their performance.

 

Nope, the flat-washer lug nuts won't work on rims that call for a 60° conical seat. You'd need new lug nuts too.

 

Main reason for wanting to use them is I have a family member who does a lot of gov't auctions and has more or less unlimited quantities, within reason, for me to have for free. All in good condition. These are both the bias ply rt II's and the newer 37'' radials. I know they aren't a super swamper by comparison. Not even close, but for tires I can slap on when I wanna play around and abuse the hell out of without any concern of damage or cost associated with it, that's all I'm aiming for. Even if I shredded multiple sets over time, there's plenty more where they came from. May even try to experiment with tire siping and redesign the highway tread centers on them. Definitely won't even see the highway though. The BFG AT's have done good in that department for me. Always gotten 50-55k out of them with religious rotations.

 

If you can get the Wrangler MT's (the directional mud terrian Goodyear had before the MTR) you will be much better off. The Wrangler MT is a much better tire than the bias ply tires.

 

Well...for that price, I guess I can say that they might be worth playing around with.
All you'd be out of is a set of rims and the time playing with the groover...which ain't all bad either. If you can groove up that center rib then you might get a little better digging action out of em too.
If they're for off-road only, I'd probably just mount em myself and throw a couple ounces of lead shot in em for balance...

Heck, I remember when I could still get belted-bias street tires for my 69 Coronet for $25 a piece. I'd burn through a pair of those every couple months just as "play tires"...was cheap fun!