Clay78

My differential makes a whinning noise while maintaining speed, any where from 25 mph on up. If you let off on the gas or accelerate it goes away. Had the diff. rebuilt during the restoration (new bearings and seals). The mechanic says he set all specifications to factory specs and that the only way to get rid of the noise is to replace the ring and pinion gear set. Since the car was not driveable when I got it, I don't know if it made the noise before. I sure hate to have to pull the diff. out again since the car is done. Have about 500 miles on it so far. Any opinions, recommendations. Also I used GM gear oil and 1 bottle of GM additive. Thanks in advance. :cheers:

MIKER

Here are a couple links from “Randy’s Ring and Pinion” http://www.ring-pinion.com/home.html

Diagnosing Noise, Part 1
http://www.ring-pinion.com/gear/g0198.html

Diagnosing Noise, Part 2
http://www.ring-pinion.com/gear/g0298.html

Clay78

Thanks Miker, good site. But they seem to have every symptom except mine......go figure :rolleyes: Anybody ever had work done at Randy's?

Jvette73

Mine does the same thing with new richmond gears. The richmond has a different cut for more strength. The drawback is this slight whinning. Change out the gear oil after break in if not already done. Youll be fine.

Steve Straus

I just had mine rebuilt. Is it a loud whining? I'm told they all whine a little bit, and you can hear it more in a Vette due to the fact that it's bolted to the frame and your sitting right on top of it. Mine had a REALLY loud howl, and after a COMPLETE rebuild just barely whines if you listen for it. It has gotten progressivly better the more I drive it. Mine was replaced with a GM 3.70 R&P, not a Richmond. It was new, not used.

PRNDL

Thanks for the links above. I get a noise.... not quite a howl, but a distinctive audible whine, only when I let OFF the gas, ie coasting, or decelleration. The noise diagnosis links say the following:

. If the gears howl during deceleration only, it's possible that the pinion-bearing preload has loosened.


I wonder what that means?? :confused:

MJ

Gordonm

It means that the pinion nut has loosened. When you set up the rears the pinion should spin by itself wit ha little drag on it. I think it is like 15 inch pounds. That is not much but there is a drag. Either the bearings have worn down a little or the nut has loosened. I have seen the nut loosen on a 12 bolt but have no experience on having that happen on a Vette rear. Same principle on both rears.

Clay78

It's a pretty loud whine. Have to turn up the stereo quite high to cover it up. If I have the gears replaced is it better to go with GM or aftermarket? :smash: :cheers:

thejaf

My 1978 has the same problem. When I was taking it to my mechanic regularly (about 2 years ago) he told me the same thing as the article. He said it's not uncommon and that it's not that bad. As long as it doens't get noticably worse, there's no immediate need to fix it. That was 2 years ago, sound still there, hasn't gotten worse, fluid is fine, etc. No problems to date.