You need to be IN the truck when back end is off the ground and powered, main reason is safety, but secondary is to feel the vibration
If output shaft wiggles then you found your problem :)
drive shaft sleeve is just to pass power, it is held in place by the output shaft not the other way around
The leaf springs align the rear wheels with the front wheels, I assume with new rims and tires the shop did a 4 wheel alignment, it is pretty standard now.
While it isn't as exact just measure from back tread of front tire to front tread of back tire on each side.
Use tape measure and put a mark at the same height on all 4 tires, then measure.
Obviously front tires need to be straight forward, and make the mark on tires low enough so body isn't in the way of front to back measurement
Last edited by RonD; 12-12-2015 at 07:50 PM.