Tire size and 4WD

I have an 89 Jeep Cherokee with smaller tires in the front then in the back. I was told by a nice stranger that I could put the bigger tires in front and still use my 4WD with out breaking anything. This goes against everything I’ve been taught, but he swore by it. He said he drove his truck like that in mud and snow for weeks with out breaking anything. So what do you guys think, could I drive in 4WD with 31"/10.5/R15 tires in front and 275/75/R15 tires in back with out breaking my transfercase? Winters coming and if I could do this it would save me some money. I don’t want to break anything.

That’s at least more than half inch of difference (31 inch tires tend to measure 30.6-30.8 inches in the real world) and the 275’s will be about 31.2 inches in diameter. This does not bode well for your transfer case. You have the old school 4WD system without a center diff, it won’t tolerate that kind of tire size mismatch.

Some “old wives” may advise that the smaller tires go on the front.
Others may advise that the smaller tires go on the rear.

Unfortunately, the vehicle’s manufacturer specifies that you need to have the same size tires on all 4 wheels, and the only opinion that really counts is the one from the folks who engineered and built your Jeep.

If you really want to save money, you will buy 4 matched tires, as any other approach is going to result in really big repair bills.

Would it work if I put 225/75/R15 on rear and the 275s in the front… I know I need all the same size; But would that work or am I really wasting my time. But would doing this in genral work or does this guy not know what he’s talking about?

225’s would be even worse, they are about 28.3 inches in diameter. You’ll save the most money in using tires of the same size.

ok well i was trying not to spend any money… and this guy told me somthing i had to check up on it… thank you every one for your advice…OFF TO THE TIRE STORE I GO!!!

There are lots of really nice well intentioned people out there…but if he’s a stranger, you’ll have no one to blame when you suffer damage. Different sizes is something you can get away with if it isn’t much of a difference, isn’t long in 4wd and only in slippery conditions. If you want to save money, do it somewhere else other than tires. They can be the MOST important safety feature on ANY car. I’d rather skimp on oil changes than take chances with tires ! It’s not only mechanical problems but traction difference you could be taking chances with in slippery weather where wider tires on the rear could “float” more in snow.

When not in 4-WD a small difference in tire size front to rear doesn’t matter. And if traction is poor the difference front to rear doesn’t matter. And even if all 4 tires are equal, driving in 4 WD on good traction will sooner or later damage the drive trains weakest link which is likely the transfer case.

right right; thats why until i get REAL tires for my jeep i am going to keep it in 2wd thanks for every thing all you great people