Tahoe Autoride

I would appreciate anyone helping me out on this one. I have a 2002 Tahoe with autoride and the front tires are wearing out (center choped due to suspension) I was told. When the front end is shaken by hand the shocks seem not to dampen the shake rapidly.The Tahoe has 25,300 miles on it and it drifts and wanders on the highway. I never go off road and just installed Pirelli scopion tires. I do not want to wear these out also. I do not like the drifting ride feel at high ways speeds and want to keep tires from wearing. The truck is still under warrenty and I am going to the dealer with the problem next week. Any predealer visit suggestions ?

I just had my 2002 LT autoride re-aligned yesterday and it helped with the drift and pull which made me look like I was driving drunk - although sober.