Dumb question....I must be overlooking the obvious. When you check pinion runout with a dial gauge, what exactly do you do? I know about putting the gauge onto the shaft, but then what? Do you turn the rear wheel and the shaft moves, or do you wiggle it in and out? [sm=dontgetit.gif]

 

Checking the run out would involve turning it. You put the button directly on top of the shaft, make sure that the indicator stem is pushed in a little so that you can see if it goes negative, then zero the dial. Turn the wheel so the shaft rotates and see if the indicator on the dial moves more than specified tolerance.
I hope this helps.

 

Yup it does, thanks.

 

Also while the indicator is on the shaft,grab the shaft by hand and move it up and down to check the axial play.