Different radius tires on truck
Getting ready to roll this afternoon, doing my last check of tire pressure I notice a screw in the tread of one of my tires. Off to the local garage and get a plug put in. Back home, hook up and final...
Forum Discussion
camp-n-family wrote:
It's the tire diameter that matters. A 20" rim can have the same diameter as an 18" because the height of the sidewall is different. For example my stock size is 285/60r20 and my spare is 285/70r18. They are within 0.3" difference and are fine to use at the same time for a spare. Most trucks with 20" stock rims will have an 18" spare.
likewise on my truck. I bought it brand new, came with 20 inch tires and the spare is an 18", regarless if the other tires are 17, 18 or 20 inch from the factory. In fact all three tire sizes have virtually the same diameter. the amount the other tires are worn compared to the spare is as big or bigger difference in diameter.
