This has been posted already but I thought I would bring it up again because I just installed springs on my cobalt ss and it has a small shake in first gear when slowly accelarating. It is noticed a little more when you back up and then go forward with you steering wheel turned slightly. Also you feel the car shake not the steering wheel. If anyone has any ideas please post.

 

does it make a little pop?

 

iknow when i lowered my cavi, there was some poppng and the ride was considerably different until my springs settled. i also get some shimmy when i accelerate but i think my problem was from switching rim size from 16s to 20s and also my rather harsh driving and shitty roads and potholes...my car is out of alignment slightly. it might just be that the springs need time to settle...
also make sure all your lug nuts are tight or that u didnt throw a weight from one of the rims.