MIAmotorsports

I was wondering what gear lube you would recommend for a rear that has some gear whine. I was looking at AMS and was wondering what kind of luck you had with the road race/drag race lube.

Bill Curlee

Gear lube is most likely NOT going to fix a rear end gear whine. The gear noise is mostly always the result of an impropery set up ring and pinion or damaged ring/pinion tooth faces (scoring)

You can change the lubricant but, i seriously doubt that it will eliminate it. Check with AMSOIL. They have a very good 75/90 weight oil with the correct limited slip addative.

BC

MIAmotorsports

I am not trying to fix it but quiet it down some. Even a little is better than nothing. It is an RPM stage 4 rear. A year old and dont want to rebuild again. I know some people say royal purple for gear noise and some aims posi additive

mchicia1

Gear lube isn't gonna do anything. I tried thicker lube once for a whining diff and it got louder if anything.

0HoosierPE

Different or new gear lube will not correct or reduce gear noise. However the wrong lube can create it. A Corvette differential utilizes hypoid gearing meaning the pinion is offset from the centerline of the ring gear. This makes for a stronger gear-set but introduces a sliding component. As a result gear lubes used in hypoid gearing must contain an EP (extreme pressure) additive. Most commercial oils today do have the EP additive however if they don't the results are scoring and noise. When in doubt check.

C66 Racing

This is the appropriate fluid, but don't think any fluid will help the noise:
AMSOIL Severe Gear Extreme Pressure Synthetic 75w90 (Product Code SVGQT)

I had an 06 CTS-V for several years (sold it in 09) and that model had many TSBs on diff whine. Many Caddy Forum members tried heavier weight fluid (e.g. 75w110) but I never saw consensus that this really helped and the increased viscosity would result in a loss of net HP and a lowering of mpg.

StrangelovesM6Vert

If lower noise is more important than losing a few hp then add some Lucas oil additive.
It's thick like honey and will absorb some of the noise.
You could also wrap some kind of insulation around the pumpkin and leave just 1 face for cooling if you're not beating on it all the time.

All together this may reduce your noise by half but won't eliminate it.

1973

I have heard of bananas

StatmanRN

LOL
A banana in the rear [no...NOT that one...] is an old used car dealer trick

But seriously: Did it always whine or is it progressively worse?
Im beginning to think a small amt of whine is inherent with Motive gears esp in higher ratios even when set up right.

jackthelad

Whine under power?

Whine on overrun?

All the time?

Nobody mentioned bearings - if the whine is always there, i.e. under throttle and under no load, bearings would be a guess.

73Corvette

I have used fine pine sawdust to quite down a whining rear end... it WORKS! Not sure I will recommend it for your Vette though....

LoneStarFRC

Hope you used clean. i.e. no pine bark beetles.

rickhimar

[QUOTE it took awhile, but royal purple seemed to help considerably.[/QUOTE]

73Corvette

Actually the pine beetle provides additional lubrication....