okay so why is it only in cold weather it feels like Im driving over rocks but not in hot weather?

Because summer compound tires firm up in cold weather. In warm weather they are in their operating range.

i was worried something was wrong with my new z all so it sound horrible when i back out of my driveway and make a turn at very low speeds i figured it was just the tires but i always suspect the worst

Normal mine does it to on a slow tight turn in cold mostly. don,t worry go have fun

holy thread necro :icon17:

Hell, I admit i was just under the car convinced the rack or other steering components broke or are failing. I just upgraded from 18 inch wheels with Michelin Pilot Sports to the 19 inch Rays with Bridgestone Potenza tires and maybe 30% tread left on them. OMG it was like freaking me out and to top this off the TPMS light came on and for 2 days after I installed them. I had it reset at Discount Tires, (FOR FREE), and the TPMS light is remaining off. Hell Yes! I must admit here in SLC, Utah, currently 27° outside I do not like Potenza tires compared to the Michelins!!!
Anyway, I thank you all for your comments and discussion as it helped me stress down so now I can go back to sleep. Ha.