I have FX4 275 65 r18 tires on my truck ( I upgraded after buying the truck )
My spare is original and smaller... 255 70 r17

My question is: Is it OK to use the spare or will two different size tires cause rear or bearing problems?

Also, I ran something over and put a 1" cut in the tread. Should I just buy a new tire or try a patch? I'm leaning toward new tire(they only have 5,000mi)

 

If you have LSD it is recommended you get the correct tire size or something a little closer ( 275/70-17 )

 

It is limited slip.Do you think the size is OK for SHORT term use? Or just buy the bigger spare?

 

Jimmy...keeping the caveat 'short term use' in mind, don't waste your money on a new spare. Just think of all the vehicles you see running around on their roller skate spares...they're not droppin' their trannys or difs.

 

I have brought this up a couple of times now but if you happen to blow a rear tire and put the spare on the tires will both be moving at different rates. When you turn the tires also move at different rates. So the LSD thinks you are turning and slipping the clutches even though you are going strait; meaning the clutches might burn up.

 

I've thought about that but, the LS bothers me.Maybe I'll price out a new spare. I wonder what everyone w/ 33"s &larger are doing?
Thanks for help asinatra.