Well, there is nothing wrong with my tires. So now we have moved on to the possibility of a bad brake rotor. I am going to replace the front brakes next week and see what that does. If that isn't it, hubs/bearing are next.

 

is there anything else that would have "moved" or "stopped" from moving the tires around? Or was that possibly just a trick of the mind? Maybe you had a tire with a few loose lugnuts? They are picky, must torque them correctly (and then do it again after 50 Miles).

Following along wondering here too.

 

We moved the wheels back and forth, side to side, every which way possible. The vibration might go away for a day, but then come right back just as before. It's not the wheels or tires.

 

you know whats funny, i have this problem too

im pretty sure its a tire though since it started when i put my aftermarket wheels/tires on

 

are you tightening the wheels to a specific torque spec or just tightening them with an impact or whatever?

have you actually checked the rotors with a dial indicator? they may have lateral run out that you cant see by just looking at them

what have you done to check the hubs out? i havnt seen any problems with hubs on these cars yet so i dunno if they'd do anything like that or not. usually hubs just make growling noises

 

Well, unless it comes back, I think I'm going to call this problem solved and give my final report.

I replaced my front brakes and it's gone. So, logically, that would lead one to believe that the brake rotors would be true when cool, but when run at sustained highway speeds, something about the heat would cause a warped condition, leading to the vibration. It fits, but it's really weird. I've never seen that happen before.

So, I'll change the title of the thread so anybody doing a search will get a good reply. Thanks for all the input people!