red xj

I was wondering what people think about the mb72 wheels. Is the weight saveings worth the cost over just geting a set of soft 8s. And how far can i air down a 31-10.50 tire on a 15x7 or 15x8 wheel. Any response is appreciated and sorry for the newb question.

junior3382

Dunno about the wheels, IMO its a personal preference choice there. As for airing down, this bepends more on the tire then it does the rim. While some rims are stonrger then others, the bead of the tire and the strength of the sidewall are really what you need to worry about. The more serious the off-road tire, the lower the psi it will run, on an average anyways. If you are looking at a rim with a beadlock opton, then that would be the exception to the rule, so to speak

I run between 14-18 psi in my tires when I wheel, depends on where and what time of year, and those are 33" tires on 15x8 rims with no beadlock but they will easily run down to 2-3 psi before any real danger...... if that helps any?

red xj

Thanks for the info. As to the wheels was just wondering if 10 pounds per wheel will make a noticable differenc.

junior3382

It will on break wear. The larger the tire, the more the weight. For example, my 33's weigh about 65lbs each. Saving weight on the wheels and tires may not show in the fuel mileage, or even in handling, but 10lbs lighter per wheel is 40lbs saved of reverse stress working against you when trying to bring your jeep to a stop. So to answer your question, saving weight is never a bad thing, but would you notice a difference in how it drives? probably not. Its a Jeep.

Rock Toy

It is hard to say if the weight savings are worth the cost increase over a set of soft 8s, you don't say how much you would be saving.
As for how low you can air down a 31x10.5 tire it would depend on what kind of tire, and which rim. A 10.5 width tire can be ran at a lower pressure on a 15x7 rim than it can on a 15x8 rim.
A bias ply tire has stiffer sidewalls than a radial tire so the radial will hold a bead better than a bias ply.
But 10 psi should work for both rims and both radials and bias ply tires. I run my 35x12.5 r15s at 6 psi in the front and 4 psi in the rear for snow wheeling and haven't broken a bead yet.