Posted by David Sherman from 208.187.13.93 (dial.tuk97.kendra.com) on Tuesday, April 16, 2002 at 2:07PM :
In Reply to: Gear Whine posted by Ira Hazan from 209.178.213.192 (?) on Tuesday, April 16, 2002 at 8:56AM :
If you're convinced it's louder than it should be (t-cases always tend to whine) and filling it up with oil didn't help, you just have to pull it out and tear it down and see what's going on.
Most likely you have some bad bearings. When the bearings wear, the shafts can move perpendicular to their axis which causes the gear teeth not to mesh properly. Depending on which bearings are worn, the whine will occur under different load conditions.
Rebuilding a T-case is not the easiest job, but it's something a normal person without a machine shop can do. Bad bearings can be cut off their shafts with a grinder if you don't have a big bearing puller, and new ones can be driven on using a piece of pipe and a hammer if you don't have a press.
The main trick is to get the right pre-load on the bearings when you re-assemble it. You do this with various shims and/or gaskets, which are easy enough to make yourself out of various materials. If you put it together too loose, you'll still have noise, if too tight, the bearings will get hot and wear out. It's a good idea to put hardening gasket sealer on one side of the gasket and non-hardening sealer on the other so you can easily take it apart and adjust things if need be.