I just bought a used toyota v6 third member with a brand new spool in it and was wondering about how much play there should be in the movement of the flange or in otherwords I turn the flange by hand and can barely turn it when I do the gears are loud. also there is NO play in between the meshing of the gears What gives? are they set up wrong? my 4cyl third that I just took out turns real easy and there is play in the pinion gear too. I can move it a bit back and forth before it moves the ring gear. What pisses me off is that I bought them from a toyota certified tech that is employed right now at the dealer, and says that he has set up tons of gears. when I drive down the road I get a sound coming from the rear that sounds like metal rubbing on metal, or a high pitched kinda quiet squeel. HELP!!!

with a spool there is only the mesh of about 12 thousands between the ring gear and pinion, there is no other gears mesh from there out, because a spool has now gears. a detroit, lockright and others all have more slack because the insides of the carrier still move to a extent. change the bearings. if it is cleaned and no fluid on the bearings (dry) that would make it hard to rotate as well.

Tight preload. Was it new setup. Then it would have tighter preload. Your old setup has alot more miles and wear then your new setup, hence tighter preload on the brgs. Toyota diffs are setup at .08" backlash. barley enough for you to tell by hand. But same deal with your old setup. Your gears have been wearing for X miles, hence more backlash. You will notice the pinion brg noise when it is dry.

What could the quiet high pitched squeel comming from the rear be? I thought it was my brake shoes cause I know Ineed to get those changed but I would hit the brakes and nothing happened (no change in noise) and the noise would stop when the truck stopped. could this be the gears or bearings grinding together? I was told that the setup only had one trip to Moab on it (from salt lake city) so probably no more than 450 miles. although the gears are older factory 4:10s everything else should be fresh and new. When I went down to moab with it installed I had no other problems other than the squeel and the fact that it got really hot! The third member and the housing were both real hot. but I did just drive aprox 200 miles non stop.

The heat is normal, my friend's Yota heats up the rearend like no other. It's right at that point where you can lay your hand on the diff after a long drive but just barely. The squeel could be a u-joint. Check that first. Chances are your rearend is fine. Like the others said, a properly setup R&P has a backlash that is barely detectable by hand.