Hearing a roaring sound whenever I'm turning left, but only at highway speeds. 2003 so tire threading possible. Didn't feel the bumpiness, but then again never felt a threaded tire. Running 19x9.5/10.5 245/35 275/35 Stock suspension didn't roll the fenders and just had new rims put on and they didn't tell me anything was up.

 

Usually, this is a wheel bearing symptom. If the noise gets worse as you turn left, the right front bearing is bad and vice versa. I would first jack up the car and turn the wheel by hand listening for any noises. Also, if you can/want, change out rims with another z owner to see if the noise goes away.

 

Jack it up and check for play.