jmballa45

I have a 94 z28 automatic. When I go over 25-30 mph it starts making a horrible whining noise. As I go faster it seems to get a little quieter but more high pitched. Seems loudest when I'm barely giving any throttle. I replaced all the bearings in the rear end and checked the gears, which had no wear ( stock gears). Now while driving it like this the abs inop light popped on. I don't know where to look anymore or have any idea what it could be. Any help? Oh and it started making the noise after flooring it one day on the highway

jmballa45

And goes away when I put in neutral

Bob@BruteSpeed

iTrader: (16)

Make sure your factory torque arm, which is made out of stamped steel, is not bending. I have seen it happen and throw the pinion angle off. Bob

Raven One

The Same thing happened to my dad after he had a new gear put in his Ford 9''. The crush sleeve wasn't compressed enough and when he put it under load it caused the pinion to move slightly causing wear and although it's set correctly now due to the wear in just the few miles he did, it still whines exactly how you've described. When you look at the gears though they look perfect. Hope this helps.

deftunes

iTrader: (1)

Did u replace the the bearing races? What preload/backlash did u set it at? And yes u might have to replace the ring gear. Even thou it looks good doesn't mean its good... how did the pattern look?

jmballa45

I noticed when I took off the driveshaft that when I turn the yoke it feels like there is a little play between when the teeth meet like it's not pushed in far enough or something.

Supers

sounds like bad pinion bearings...but im not there looking at it myself, but it sounds like bearings

jmballa45

Guess I'll just replace the gears and hope it fixes it

deftunes

iTrader: (1)

did it whine before your bearing install?

if it didn't it's just backlash and preload you have to worry about.

jmballa45

Yes it was. I explained everything that happened in the first post

deftunes

iTrader: (1)

It seems you don't know much about differentials. You should take it to some one who knows what they are doing...

jmballa45

Well of course i don't know much about diffs. That's why i posted in here....