Hey, We're driving across Canada and the Suburban was running great until we picked up an odd vibration that I think is in the drive line. At about 100 Km/h the vibration starts and gets worse upt to about 110 then fade back off until it's relatively smooth again at about 120. The best way I can describe it is a combination of a wheel needing balancing and running over those idiot strips that mark the shoulder on some roads. The vibration is not in the steering wheel an seems to come from the chassis and under the floor. This truck got a new engine and transmission a few months ago along with a new front drive shaft (reman on the shaft actually) and new rear u-joints. This is a small block truck, originally a 5.7l but now a 6.2l (HT 383E upgrade crate motor) and the Trans is a new 4L80E. This is not an Autotrack vehicle. It has a manual 4x4 shifter on the floor. Any ideas on the cause of this? Anything I can try on the road? I have a basic tool kit (sockets, wrenches, screw drivers, multi-meter) Going to try and make it to a dealer nearer to home, but that's still a 10 hour drive. Any help would be appreciated.