Replaced a single tire

[grayj1979]

Hey folks. Ran over 3 nails and had a single tire F'ed beyond repair. I was blocks from some local tire place and bought the only 245/45 20 they had in the shop.

So now I have 3 conti extreme contact DWS06's with about 25000 miles on them, and a new/fine but rando tire on passenger rear.
Obviously this isn't ideal as far as performance and not the long term plan, but in the short term, am i stressing the PTU/ rear diff because of the size differential because of wear? Trying to decide if i need to go ahead and buy a new set this weekend.

 

[jman1200]

Not gonna say its good or bad but will let you know that my SHO had a brand new tire (same brand/ref as the others) at the front when I bought it. 3.5 years later, tires are due for replacement and (knock on wood), no PTU issues.
Used to have a Sienna AWD in which I once replaced one tire after hitting a pothole. Never had any issues

 

[Johnsho2016]

Hey folks. Ran over 3 nails and had a single tire F'ed beyond repair. I was blocks from some local tire place and bought the only 245/45 20 they had in the shop.

So now I have 3 conti extreme contact DWS06's with about 25000 miles on them, and a new/fine but rando tire on passenger rear.
Obviously this isn't ideal as far as performance and not the long term plan, but in the short term, am i stressing the PTU/ rear diff because of the size differential because of wear? Trying to decide if i need to go ahead and buy a new set this weekend.

I blew up my PTO with two front tires that were 10K miles newer and ford would not replace it under warranty because of the diff tread depth. Just what happened to me. So ever since then when I have 1 bad tire for something like what your dealing with I replace all 4.