Gmc death wobble

[Alvi 812]

I have 2015 3/4 ton duramax. Dealer lifted 4inch on 35x12.50. Truck has 35xxx miles never leaves blacktop, your typical mall crawler. My front tires started rubbing fender wells around 28xxx miles, so i had my local gm dealer turn up the torsion bars slightly, and then do an alignment. I recently Put new set of tires on and all hell broke loose. First it was pulling to passanger side something fierce, and has a wicked vibration through steering wheel and a case of the death wobbles to top it off. I immeadiatly pulled off new tires and put a set of stock/oem wheels and tires on, they have no effect on drivability. Still terrible, after 4 alignments, two new upper ball joints, torsion bars adjustments, new pitman arm and idler arm,truck still pulls to passanger side and is experiencing death wobble around 45-70 mph. Dealer is now leaning towards the front axle shafts being the culprit thats causing the wobble. Any one else experienced front end issues as this? Input much appreciated.

[gearheadesw]

Did you check the upper and lower control arm bushings? Could they have missed a bad wheel bearing.