Ok so I know that if you run differant size tires from front to rear in 4wheel drive you will blow your gears becasue your ratio will be off.

My question is. I am going to buy 18in rims and put 35in tires on them. Would it hurt anything to get a 35in tire of the same brand but on a 17in rim to put on my stock spare for the purpose of having a fullsize spare with me?

The 17's are cheaper and I can't see spending the money to put a nice rim under my truck for those "incase" moments. Nor can I afford it.

 

all that matters is the outside diameter. Dont see why you couldnt do that.

 

The size of the wheel is not important. The only thing that matters is the overall diameter of the wheel/tire package; they have to be equal.

 

Get the OD of the spare close, it doesnt have to be exact and the truck doesnt care if it's a 17, 18 or 22 in rim...just not a 16!

 

Great thanks guys.