Spare Tire Size

I'm getting ready to purchase new tires and switching from 275's to 265's. My spare tire is a never used 275 and I was thinking about just keeping it to spare the expense. If I get a flat and have to use it, does it matter if my spare is bigger than my current tires?

Also, why aren't my title letters in bold like everyone else's when I post a thread lol...

 

I hear conflicting info on this, but it seems like it should be ok if you will only drive on it the minimal distance to get to a repair facility. I wouldn't want to travel long distance with a mismatched spare. The idea is that the size difference will overwork the differential as the tires will spin at different speeds.

Also, the threads you haven't looked at will be in bold. Any title that isn't bold means that there haven't been any new posts since you've looked at that thread.

 

Ahhhh thanks, I kept trying to find a way to bold the titles lol...

 

The computer will think one wheel is spinning faster than the other and might attempt to trigger the stability control program.

Not sure what the delta has to be but a mismatch in tire size should trigger it.

 

The difference in diameter is 32.2" (275) vs 31.7" (265). When the 265s are brand new the difference in height would be 8/32". A ballpark depth to replace tires is when they have around 3/32" or 4/32" tread depth remaining. The oem tires tread depth was around 12/32" (I think), so it would be like using your unused oem spare when your oem tires were ready for replacement. It probably wouldn't hurt to use for a short distance to a tire store like Thatbassguy mentioned, but as your new 265s start to wear, the difference in height will only increase. I would want to replace it with a new 265 spare, but that's me.

May as well do a 5 tire rotation. Your set of tires will last 25% longer. It's not a good idea to keep a spare tire long term, even if it isn't used. Rubber dries out after a while.