Originally posted by raging56:
My best guess was use the spare until the rest of my tires need to be changed. But, will I be causing any damage having one new tire and 3 tires with 20K miles on them?
The problem with that, is that it doesn't sound like you intend on replacing the spare.
You need to buy at least one new tire. I'd match the spare (assuming its new), use the two new tires, and switch the left over tire w/ 20k to the spare. Actually, I'd probably just use this as an excuse to make an upgrade and get a new set of tires. You got 20k out of the stockers right?