Just got a new set of Toyo O/C A/T's (best tire ever ) in 286/75/17's. Makes a huge difference in looks (better) and noticable difference in braking( slightly more effort.

Now here's the question: My spare is still stock size. (255/65/17) If I happen to get a flat on the rear (have LS) would I be safe to put the 255 on the front in a 'get home' capacity?

 

It'd be fine to drive. Now if you had a locker in the rear end, then you'd be screwed.

 

Yeah, you should be fine. A lot of people say you can't run two different height tires with a limited slip or locker but every performance car I ever owned had limited slip and came with a mini spare.