Sorry for the silly question but if I have a single, unrepairable flat tire on the Cayenne, do I have to repair all four?

This is our first AWD car, and one of the guys in the office was telling me that if you get a flat tire on an AWD car, you *must* replace all four or else you risk damaging the AWD system.

Is this true of a Cayenne?

My car is an S w/o PASM.

 

It's possible on some vehicles that it could happen. Audi and Subaru are very sensitive to it, Porsche not so much. You should replace at a minimum pairs unless the other tire on the axle is almost new itself.

Have no fear, I can sell you a new tire and shave it to the tread depth of the other three. We charge $25 to do it and can cut to any depth you need in 32nd's of an inch. Just get me an average depth (a local tire shop or auto parts store have depth gauges) and call me.

 

i'd rather replace a pair than shaving a brand new tire...

 

Thank-you both... looks like i'll be replacing a pair then

The spare "used" tire should come in handy in case any of the front pair get punctured or damaged over the winter

 

Really???

I find this 'same axle' argument interesting as well, and it almost is like a 'lets hit them with the all 4, then back down to the same axle and they'll go for it thinking it is a reasonable compromise'...Is there a technical reason that a front to rear is OK but side to side is not?

And lets discuss what this 'mismatch' really is...

Rationally, looking at a 28" diameter tire, a differential of 1/32 of an inch is about ONE revolution per mile in difference. (0.1 inch is about 3 revs, so 1/32 is one rev)

I just can't believe this from an engineering point of view. Porsche BY DESIGN allows a 0.1 inch in front to rear mis-match on the 996 front diff, which is 3/32. and many many people run 0.3" differences which is 9/32.

My 2 cents.

A

 

That's what I recently did too ... and I do this on 2-wheel or 4-wheel drive vehicles.

 

do not talk to your guy in your office about tires and awd system