Is the ring gear and pinion hard to set up on a 4640?  Never done one.  I know you  have to pull the axles.  I think I  have the parts in the burnt 4840.  The ring gear does not show any marks, but the pinion gear out towards the point has several pits in it. Didn't tear it down for that, tore it down because the transmission had locked up.  It wasn't C1 or C2, but the sun gear had busted.   Since it is pitted, thought I would replace the ring gear and pinion as well.  Thanks for any help.