Ok guys, turns out it may be the drivers side front shock. I had suspected it for some time. I took the Tahoe to the local Chevy dealership for an oil change and to get it up on their rack. They did so. Couldn't find squat. Ball joints, good, bushings good, linkage good (I just replaced the pitman and idler arms). They put two mechanics in the tahoe and went for a ride. Came back and told me they think it is the front shock. So contacted autoanything.com where I bought the shock. To exchange the shock, I had to first buy another. Then send in the bad shock to autoanything. They in turn send it to Bilstein. If Bilstein finds the shock fits their 'failure criteria' I'll be credited the amount. What the **** is that! I have to pay the shipping back to autoanything.