Rear differential noise at 30-50 MPH

[dmatchett]

One of the most common calls the sales staff get is when our customer installs a new ring and pinion and every thing sets up fine, proper backlash, good
pattern, etc but still experience a whine when test driving the vehicle for break in and has a whine at 30-50 MPH on and off the pedal. This is a common
issue with aftermarket ring and pinions, simply disassemble the job and add .002" shim to the original pinion shim, this will move the pinion deeper into ring
gear enabling more contact. I recommend doing this with the original setup to save time and labor, keep in mind letting the job go and advising the customer that the noise will go away, that will not happen and if he returns after to much mileage has been driven, the ring and pinion will have to be replaced. The setup will not be affected from doing a test drive because the break in has not been completed thus allowing for correction of the settings.

[carod]

Great Diff Info and posts.
Thanks