Anyone having problems with a vibration on G8 GT?
I have a 2009 G8 GT, 1SC options package, had it for about 40 days and the GM dealer I bought it from has been trying to diagnose a vibration. They've re-balanced, done a road-force balance, switched out different tires/rims, etc, but it still persists, sometimes you feel it in the steering wheel, sometimes the whole car vibrates, speeds vary at which it occurs, but is generally from 70km/h and up. Could this be a driveshaft issue? Anyone else experiencing this? The Dealer is going to help for sure, but just thought I might not be the only one... Thoughts?
Other than that, car is an overall amazing value and vehicle, I love the space as I am quite tall and people can still fit in the back, and hey.... gotta love the V8. (Getting decent gas mileage, too!)
Also, has anyone added subs/amp? I don't want to mess with the dash, but it defintely needs a more well-rounded stereo.