I don't think replacing all four is necessary, however if the overall tread depth difference between the replacement tire and your current tires is pretty large, I would suggest possibly shaving the tread to match the rest. Tirerack offers this service.

http://blog.tirerack.com/blog/make-d...on-an-awd-car-

 

Yep looking into tirw rack shaving service as I type this. Anyone have actual experience with how it turns out?

Doesn't Infiniti have like an official recommended tire tread difference between new and worn tires allowed on an AWD car? Doesn't say on the manual what's tolerable.

 

i think if you went with a 80% worn tire and a brand new one..it would still be in spec..not 100% on that one.

 

Sigh... I'm looking at buying 4 new tires... the price of a new single tire shaved and overnighted is about 200... 4 new tires are about 400...


Btw, I know subarus (hate the cars, and their commercials) need to pull the fuse and turn off AWD when using spare donut tires... do our X's need anything like that? Or is it slap it on and go?

 

Slap it on and go. You're only driving 90miles. The AWD G is RWD bias so the front diff. won't engage unless there is rear wheel spin.
Regardless, the spare is the correct size even if the AWD kicks in.
Don't worry about it.

And, fwiw, when I had my X it had one tire damaged from a large nail through the tire wall and wasn't safe to repair. I bought a new pair of tires (same brand/model as OEM). The existing, semi worn tires were within 1/8" (3.2mm) the tread of the new pair. This was the dealers recommendation in Guelph. I drove on the tire combo for two more Spring,Summer and Falls.

 

Sorry, misread.

 

Pulled the trigger and ordered new tires... bad thing is, I have to wait a week cause there were none around the stores I went to.

Question is... will driving a week screw up my AWD? I already have 300 miles on my car with the damned spare...

 

I don't see why driving on the spare that came with the car would necessarily hurt it but I would refrain from driving when possible.