I've got an 07 2500 CTD and just had a 6" superlifts kit along with their dual stablizer bar installed. At the same time I had Mickey Thompson Baja Claw radials put on. Now the interesting part, when I'm going down a free way or generally over 40mph, and go over a bump/crack/expansion joint on the road my truck goes into an unreal shaking. Think going over really bad washboard gravel road. The company that installed the lift says it's the tires, every tire place in town says there's no way those tires should do that. I haven't been able to find anything on the internet of somebody have the same problem as me so I'm going to try this site. Any advice would be much appreciated.
Devin

 

I have experianced this, check the torque on the control arms. I found that the shop that did mine, didn't locktite the bolts. so they were loose. I cleaned the threads, and alignment cams. then applied blue locktite, and had no probs till today ( 5000 miles later ) and it felt like it was happening again will use red locktite this time.

 

also check the track bar... i doubt it has wore out on a truck as new as yours but those ball joint type ends on the end of those wear out rather fast and can cause it to happen

 

I just took one of the installers for a little ride and scared him senseless, he also figured maybe the trackbar, but monday they're going to check all of that over again and then they're going to try replacing all the shocks and see what turns up. Anybody that I show this problem is just baffled.