Ok i had a nail in my tire.. the Goodyear shop told me it would not be able to fix because it was side wall damage.. So i was planning on changing just the two rear tires but he said for awd cars when you change tires you must change all four because if two of the tires tread is lower than the brand new tires it would ruin my transmission/axles even with the same size and same brand tires. Can anyone confirm this before i decide what to do. Thanks

 

You are not supposed to run different size tires f and r or staggered, BUT,
If your tires are not worn that much and you put the very same make and size of new tires on I can't see this causing a problem.

 

Found an answer for a similar question here:

http://autorepair.about.com/library/a/1/bl237.htm

Seems like they're not lying to you....It's about a Volvo, but same concept. Although the G35X is inherently rear wheel drive until slippage is detected....

 

Ahh i see yeah i was thinking since the x is only awd from 0-15 mph and when it detects slip it would not cause a problem also the front two tires have a goooood amount of life in them i'll just settle with two for now i guess .. thanks