Ok I've searched and searched but found no conclusive answer, I have an 06 pre runner reg cab. I put a 3"/2" lift on over a month ago and ran factory tires up until about a week ago. Ok so I've always noticed a little slop in the driveline before the lift if I started off on a hill or dropped the clutch a little you would get a pop from the driveshaft, at certain speeds just letting off the gas would cause a little rumble. Post lift on factory tires the driveline shudder showed up along with a 40mph+ vibration barely noticeable but there. Then came new wheels and tires and a significantly louder roar and vibration at highway speeds, now after a little over a week the roar and vibration is seriously worse, at 70 mph the radio will barely drown out the roar. I installed 2 degree axle shims this evening which helped the takeoff shudder, but the high speed roar is he same if not worse, since I have a pre runner I can't flip the driveshaft, what else can I do I'm going to replace the ujoints tommorow, but beyond that I don't know anything else that I can do.
Kind of frustrating spending all that money just to have the truck nearly undriveable. Any input would be great.