So I have 31 x 10.5 on/off road tires all around, on 15" wheels. I'm thinking about upgrading, but I'm having a hard time finding lots of options. I want to keep the same diameter, 31". So what I'd like is to replace my 15x7" wheels with 17x7" or maybe 18x7" wheels. And then wrap 31x17/18" on them. But I'm having a hard time finding many tires that will fit on larger wheels.
My original plan was even more aggressive than that. I originally wanted to upgrade to a 18x7"s in the front, and 31x10.5r18 on the front, but go wider in the back. SO figure something like 18x9" wheels, with 31x12.5r18 in the rear. My rear wheels are naturally set in a few inches more than the front, so the width of the back would depend on how many inches i need to add to get them to "stick out" just as far as the front, plus however many inches IN i can go in the rear without rubbing. 31x12.5 should be easy, 31x14.5 may even be able to fit if I can get the right wheel backspacing. It seems like wheel and tire options are VERY limited if you want to go bigger than 15".
Another issue I'm not so sure about is metric tire sizing. I get how it works, it's the width in mm, then the % of that width as the sidewall. But doesn't that mean that it's almost impossible to get two different tires with different widths, to be the same height? Different height means different circumference, and 4wd won't work too well with that. Is this a known issue with having wider rear tires?
Also, lastly. . . .
Truth be told, I don't have a jeep! I have a ZR2 Blazer and my 31x10.5's are factory. But I'm not finding much info on Blazer forums, and I figure who upgrades their wheels more than Jeep owners! If anyone knows about these wheel and tire sizing problems, it will be people on a Jeep forum
So I've browsed the websites of a lot of aftermarket wheel makers, and they all seem to have a few options for each wheel design but not much. Are there any wheel makers that do semi-custom wheels? Meaning, not a custom design, but they make their standard designs with the width and backspacing of my choosing? I'm not looking for anything fancy. Something 5 star, not chromed. If I go with the easy plan, it would be something like 18x7 with 4" backspacing. If I go with the cooler plan, those would be the front and the back would be something like 18x11 with maybe 2" backspacing, so the wheel would be 2" wider on the inside and the outside. (All this wheel stuff is assuming I can find suitable tires to match.)
Well, I'd just like to say that I'm not ignoring you. I simply don't have any decent info for you. There are tire size calculators all over the web that can help you compare dimensions of various tire sizes. I like this one when having to fiddle around with metric sizes--http://www.miata.net/garage/tirecalc.html I haven't much knowledge about aftermarket wheels either as they never interest me. Around here, most guys either stick to OEM Jeep wheels of various designs (like me; Jeeps do have relatively many nice OEM wheels to choose from, so we're lucky) or go the fully uninspired/cliché route of Cragar Soft 8's/D-windows (and look-alikes of other brands) with the occasional Dick Cepek DC2 in there.
I do appreciate you coming to Jeepers for this info, and it was a pretty clever idea. Hopefully someone around here can help you out. Perhaps check with hot-rodders for info on wheel manufacturers that might be able to provide custom width/offset/backspacing. It's quite common among hot-rods and old muscle to run two different sizes.
It may not be a Jeep, but I have respect and appreciation for a nice ZR2. Posting pics is practically a law around these parts, so why not introduce your Blazer to us?
I think for a 17" wheel, you would need a 245/70r17 to get a 31" tire. Most 31x10.50r15 tires are less than 31" tall. if you look at a tires specs, the manufactures list a revolutions per mile and a listed diameter of the tire. I looked up the specs of these size tires, same model, tread pattern etc and the 245/70r17 is 0.1 taller, and 1 rev per mile more. Often you will have a greater difference than this from one company to the other in the same size of tire.
Also you could go with a 255/70r17 which is about .5" taller, but just a little bit wider
255/70/17 gives me 31.1"x10"R17. I'd definitely opt for that over the 245/70/17
So when it comes to revolutions per mile, first off how do you find that spec out in the first place?
And how close do they have to be front in back, for a 4wd? Is going with wider rear wheels common on jeeps?
265/70/17 Works out to 31.6x10.4r17 . That's a good size, assuming I can find some properly back-spaced wheels to upgrade to.
You guys don't have this problem but all the full size chevy's, all the Colorados and all the Trailblazers are 6 lug wheels. I'd love to upgrade to some nicer, newer chevy wheels but as it turns out, my only real options are old corvette wheels. S10's only ever came with 15"s, and a few 16"s but the 16"s don't fit 4x4. :/
I've never seen a Jeep run wider rear tires. I personally don't see a point in it either, but accept it as your choice if it's what you want to do. As someone who has to deal with a lot of road driving and snow, I always shoot for the narrowest tire I can.
How close [in diameter/circumference] should they be front to back? You should shoot for exactly the same. I'm not sure what kind of 4wd you have. A part-time 4wd system (front and rear locked together) will not be happy with anything except an exact match. A full-time 4wd/AWD (transfer case behaves as an open differential) could tolerate a little difference I think, but I'd still not risk it personally.
Don't 4th gen Camaro (93+) wheels fit 4x4 S10 Blazers? I'm pretty sure they do.
This truck is not my daily driver. It's my boat puller slash alternate vehicle. Bigger back tires is just about getting as much traction as I can. ZR2's have a locker in the rear, but bigger tires will just give me that much more traction. I was thinking about putting a limited slip in the front too. And it is part-time 4WD. While I don't do hard core off roading with the truck, I can see myself launching and retrieving my boat in some pretty sketchy places. Can't have too much traction. Plus when it snows etc.
But about front and rear being exactly the same. That seems impossible given that the Diameter of the tires is no longer the dimension. With the metric tire measurements, making the tire wider changes the calculation to get the diameter. And since they round numbers to 5's or 10's, it's seems impossible to get two different width tires to have the same diameter.
Most likely it's a moot point, because I'm thinking I'll never find proper wheels for this unless I go totally custom, and I'm not going to do that. But in my dreams, I have 31x10.5 in the front and 31x14.5 in the rear
Also what I've read is that 2wd and 2wd blazers (and s10 pickups) use different wheel spacing. So Camaro wheels will probably fit on a 2wd blazer fine, but will probably stick way out in a 4wd.
See, I've found the exact opposite LINK--that Camaro wheels work great on the 4wds but are a bit goofy on the 2wds (curse you for getting me all wrapped-up in this ). I could be wrong, but since I've seen a number of build threads for Blazer Xtremes using spacers to fit Camaro wheels, I think the claims in that link are legit.
Have you played with the tire calculator I linked to find any differing metric sizes that match-up in terms of diameter? 4wd systems pretty much are why 4x4s never have different sized tires front-rear though. If traction is all you're after, playing around with wider rears and narrower fronts is just creating an unnecessary headache for yourself especially if boat launching, albeit sketchy, is your primary challenge. A good tire will simply be all you need--some extra mm of width in the rear really isn't going to make or break your traction.
If all you're ever doing is popping the 4wd on for short moments when at the boat launch, a little difference in tire size front-rear shouldn't be a big deal. You won't be moving large distances causing your xfer case to bind much if at all, and the ground should be rugged/slippery enough to allow your tires to slip a bit to compensate as well. Just don't ever drive long distances in 4 in this case, and, like always even with same tires, don't drive on dry pavement in 4.
So after lots of searching, I did eventually find a set of 18" wheels I like (American Racing Axl) 18x7.5". Some would call them a 10-spoke, I'd call them a doubled 5-star. They're thinner than most 18's, but they're not "thin" in a general sense, they're actually half an inch wider than my stock wheels. And I found some 275/60R18 all-terrain's I could put on them. They are Yokohama Geolanders. They don't quite have the nice aggressive look of the stock BFGoodrich tires that ZR2's came with, but they are the only All Terrain 31x10.5R18 equivalent tire I could find. They look like a pretty good match, visually and spec-wise. Now I just need to wear out these old tires I have, so that I'll "need" new tires
Here's a link to the wheels: http://ipsite.org/1gnw
I think they'll look good. And maybe I can find some chevy logo center caps that will fit in place of the AR centercaps, to give it more of a factory look.