[DAVZ289]

Hey guys--

I am getting some decent whining noises from the differential and I need some help diagnosing them. This is an 8" rear with a freshly rebuilt 3.55 traction loc center. Upon acceleration, and when holding at a constant speed, there is a whining/droning noise coming from the differential. This gets louder until about 50mph, and then tapers back down and at about 60mph it is gone. If I "feather" the throttle it will whine, and then back off. Any ideas? I was thinking maybe axle bearing, but those were both just replaced too. There is also a good amound of chatter when turning corners, but I am guess this is because the clutches are not broken in yet. Any ideas on the whining?

Thanks
Dave

 

[sharkmouth]

The gears are set up wrong or cheap gears...drive it like that for long and there will always be whining with those gears

 

[camachinist]

Were the gears new with the rebuild?

Running the car on stands will unload the axles and should help to eliminate the axle bearings from the equation.

You may have to pop the differential and check the tooth pattern on the ring gear...it's remotely possible they set the gears up wrong. If so, back to the vendor they go.

If the gears were used, unfortunately there is very little you can do if the tooth pattern looks OK....that's why I always recommend new gears in a street car.

BTW, with nearly 200K on them, the gears in the 8" in the D-coder are just starting to make a perceptible whine at certain road speeds, though not all the time. Gear noise can be one of those things we get used to, like loud mufflers..*G*

I think if you run the car up on stands and do some poking around with a mechanics stethoscope, you'll find the root of the problem...

I'll assume everything else went well, yes? I recall working a trans or engine issue on your car recently...

Good luck!

 

[DAVZ289]

The gears are (were) brand new Richmond ring and pinion. There is probably somewhere around 100-150 miles on them now, including the drives I took to break in the gears.

You are correct, you replied to a post about a trans problem I was having. I did post again under that thread, but it is so far buried at this point that you probably just missed it.....

The fluid level went back to normal, perhaps a bit low. The shift quality is really good, so I am not to worried there. There were a few bubbles in the fluid on the dipstick, and with all the rear end noise, I cannot tell if the tranny is causing some of the whine or not.

Thanks Pat

Dave

 

[camachinist]

Isolating the noises to the rear end with a stethoscope should assist in determining the location and severity of the problem.

If you find the differential area to be the source, I would suggest contacting the assembler and getting their advice regarding how to proceed next. There are steps you can take but, IMO, and remedial work should be handled by the vendor.

I'll surmise you have a pretty penny in the differential so it's incumbent upon those who you paid to make it right.

If you need any further assistance, post...