chris2523
93 Mark VIII
Yeah, totally agree there. Definitely match the diameters on the back. I guess I was always under the assumption that the traction control on our cars gets temperamental when different tire heights are used on the front compared to the back when beyond a certain percentage, apart from the whole issue with mismatched tires on the back of a RWD car.
If the tire height of your spare matches the height of all 4 tires you are running, it doesn't matter where you put the spare for temporary use. I have found that a full size spare works well in this case. My current spare tire is an old drag radial. Kind of stupid LOL, but I can put it on any corner of the car if I get a flat and the tire height is only off by 2 tenths of an inch. It'll look wacky as hell on the way to the tires shop but it'll get the job done and I don't have to mess around with swapping tires around.
Now IF that 2 tenths of an inch between both rear tire heights is enough to mess up my differential if it happens to be a rear tire that goes flat, I will surely change my ways! I guess I haven't had the chance to test out that theory but I would imagine it would have to be more significant than that.
taller in the back. if the tires are mismatched, and the back is taller, you will be ok.