I recently installed some new bearings in the rear end.. I followed the assembly manual, using the factory shims in the correct places and torqued everything down as specified.. the car makes no noise while accelerating or going slowly.. or while decellerating.. however, I noticed a high pitch sound while going about 45 mph and higher and a constant speed... its like the sound that is produced when you run your finger around the rim of a crystal glass.. a high pitch hum...


if I push the clutch pedal in at that time it instantly goes away.. I think its related to the rear end since I just installed the new gears but I can verify the sound is comming from there..

any ideas? This is a bit frustrating..

thanks!

 

differentials.com might have some useful information.

I have a question for you. My differential pinion seal is leaking and it still leaks even after I've replaced the seal. The pinion seems to have about 1/4" of little play in it so I assumed the bearings need replacing. I want to do this myself but just how difficult is it? I have a torque wrench as well as a "in-lb" torque wrench, but everyone I know is scared to touch a differential. Did you replace your own bearings or did you have someone else di it, also how hard was it to replace. Thanks.

Mark

 

I'll do my best to answer your questions here:

If you have an in/lb torque wrench it will help alot.. also I have a 20 ton press (you will need this to get the bearings races on/off the pinion bearing/side carrier bearins)and a compressor and a pretty powerful impact wrench (over 500 ft/lb max torque). I also custom fabbed a special tool to hold the yoke in place while I tightened down the pinion nut.. These last two appear to be the real critical portion in that the GM axles use a crush collar which is quite difficult to crush down to spec.. then once it begins to tighten down you dont want to over tighten otherwise you will have to disassemble the pinion and either buy a new crush collar or put yours on a pipe and bang it out a bit so it has room to crush to the correct size..


The other thing I feel nessesary to note is that I reused my stock gear set (3.23) which makes things a bit easier.. in this case you can reuse the stock shims and you should be dead on with the pinion/ring tolerances... its is important to remeber to keep the shims for each side of the differental carrier side bears on the respective sides than came from. Also, dont loose or damage the pinion shim that is behing the rear pinion bearing race..


lastly, please ntoe the problems I'm having above.. I'm not sure i did everything correct.. it would help if you could have somebody handy who has done it before to make things go smoother!

hope this helps!


now anyone know about that high pitch noise i'm hearing?

 

anyone?

 

did you get any resoulution to this?

i'm having the same problem

 

Sounds like gear whine. Did you run a gear tooth pattern when you installed the gears? If not you might want to do that. If you did and it was good it may just be the gears. Some gears are noisier than others. I hear richmond gears are noisy. Anyway, good luck with it.