Car "Hopping"

[Hecubus84]

Just because it's new don't assume it's good. I've read a few threads where people are complaining of vibration issues after installing a aftermarket driveshaft. If you still have your stocker try installing it to see if the vibration disappears. I'd also consider having your tires rebalanced by an outfit that has a road-force balancer. I had a bad imbalance on my car after getting two new tires installed, I then balanced them at my school and found they were both off by about 8oz.