[ChrisCNC]

I agree, Ridgerunner. Just had the exact thing you've described, 1st gear towing up a steep incline (23% according to google earth) was unuseable. Took it in and they found the driveline was twisted over 2 degrees, plus the carrier bearing was mis-aligned due to my 5" FabTech lift. Got the driveline fixed and balanced, and the carrier bearing aligned and the takeoff vibrations almost completely went away. They still exist but are barely noticeable, my tranny guy said I really need to get a torsion bar to prevent the rear-axle/differential from torqueing under load and he thought that would remove the rest of the vibration.