what is the diffrence of running a 33x12.5 15 on a 15x10 or running a 33x12.5 15 on a 15x8 rim? my plans are for off roading on muddy trails up a mountain. i have a 95 4runner 22re. sorry if this question has been asked before.

 

pretty much the same however, with a 10" wide rim the tires might rub more as they are wider......

 

For most offroad use, running a 12.5 tire on an 8" rim works the best. It lets you air the tire down more w/o loosing the bead. And the tire bulges out to the side offering more protection of the rim, less likely to ding the rim up on rocks or to jam mud and what not in between the rim and bead. I have heard that folks who want more flotation in sand and other soft terrain prefer the wider rim. Gives a little wider and flatter tire footprint. Also makes the sidewalls a little stiffer for better on-road handling and the flatter footprint gives better treadwear as well.

You can kind of see the difference with the pictures on this page, 15x6 wheels w/ 9.50 and 10.50 tires mounted (I know it is not a 12.50 tire and an 8 or 10" rim - but it is the same wheel-rim width difference that matters):

http://www.4crawler.com/4x4/BFG_AT_KO.shtml

I've run both size tires on the same wheels and vehicle and I did find that the 9.50/6" combo gave more even tread wear on the road, while the 10.50 tires wear a lot faster in the center of the tread. The 10.50 airs down a lot better than the 9.50.

 

thanks jimabena74 and 4crawler

 

The tires will be fractionally taller on the narrower wheel also.
I think???

 

yeah, that sounds about right

 

ok here is a picture of an explorer with front 15x8s and rear 15x10s... both are 33x12.5 for size comparison