Originally Posted by GSS138

I really don't think it's tires at all, but change them if you know they are bad and if you have the same problem then it is something more serious.

I ran my last set of tires into the damn dirt before I swapped them 3 weeks ago because my race shop guy told me explicitly "Do not go to the track again on these tires!"

If you have OEM sways, and low mileage like you are talking about, then something is wrong back there and needs to have someone professional look at it. If the tires don't fix it, then you have something loose in the back end that needs a real suspension tech that knows the 370z. If the tires make a vast improvement, then you need to take your rear camber down to like 1.3 and stop buying sh`tty tires.