differential whining at speed
Thread Starter
Advanced
Joined: Dec 2007
Posts: 52
Likes: 0
differential whining at speed
I have 2003 AE with automatic transmission, 35000 miles. Recently the differential or transmission suddenly begin whining. Began as low pitch whine then went to higher pitch after a few miles. Maintained the higher pitch until I got it to GM shop. Whines in any gear at any speed, pitch does change at various load and speeds. No whine at all during deceleration. GM dealership has removed diassembled and inspected both differential and transmission without any evidence of cause. They now suggest replacing the differential ring and pinion etc. I think they are just shooting from the hip. Help please!!! I must approve further service on Monday July 27th.
Tech Contributor
Joined: Oct 1999
Posts: 41,037
Likes: 9,799
From: Charlotte, NC (formerly Endicott, NY)
It all depends on loud it is. If not all that loud (other people than you don't really notice it) I might be tempted to let it go until it gets really loud. Sometimes things like this can go for years before they get bad enough to really cause a problem. My 97 Olds Bravada developed a whine in one of its diffs when it had about 40K on the clock. The dealer recommended waiting. Five years later I sold the vehicle when it had 95K miles on it and it still whined about the same.
If you have it repaired you could end up with a worse problem. Even the best mechanics don't repair/adjust many differentials in a year. Diffs just don't go bad that often so they may know what to do but may not be all that experienced in working on the Vette ZF Diff which I understand requires some special setup tools Vs other diffs.
Bill
If you have it repaired you could end up with a worse problem. Even the best mechanics don't repair/adjust many differentials in a year. Diffs just don't go bad that often so they may know what to do but may not be all that experienced in working on the Vette ZF Diff which I understand requires some special setup tools Vs other diffs.
Bill
Melting Slicks
Joined: Jul 2007
Posts: 2,939
Likes: 7
From: Simpsonville SC
St. Jude Donor '09-'10
I had a brand new 3.73 gear from RPM Transmissions. After less than 400 miles, it started to while. Around 30 MPH, you coulod hear a low-pitched while. The faster I would drive, the higher the frequency and louder it got.
RPM confessed they had a bad series of ring and pinion gears from their supplier. They replaced the whole thig with a 3.42. No more problem.
I woud agree it is your ring and pinion based on my recent experience. It if is out of warranty, consider going with a performance diff rom RPM!
RPM confessed they had a bad series of ring and pinion gears from their supplier. They replaced the whole thig with a 3.42. No more problem.
I woud agree it is your ring and pinion based on my recent experience. It if is out of warranty, consider going with a performance diff rom RPM!
Thread Starter
Advanced
Joined: Dec 2007
Posts: 52
Likes: 0
It all depends on loud it is. If not all that loud (other people than you don't really notice it) I might be tempted to let it go until it gets really loud. Sometimes things like this can go for years before they get bad enough to really cause a problem. My 97 Olds Bravada developed a whine in one of its diffs when it had about 40K on the clock. The dealer recommended waiting. Five years later I sold the vehicle when it had 95K miles on it and it still whined about the same.
If you have it repaired you could end up with a worse problem. Even the best mechanics don't repair/adjust many differentials in a year. Diffs just don't go bad that often so they may know what to do but may not be all that experienced in working on the Vette ZF Diff which I understand requires some special setup tools Vs other diffs.
Bill
If you have it repaired you could end up with a worse problem. Even the best mechanics don't repair/adjust many differentials in a year. Diffs just don't go bad that often so they may know what to do but may not be all that experienced in working on the Vette ZF Diff which I understand requires some special setup tools Vs other diffs.
Bill
Race Director
Joined: Jul 2004
Posts: 16,795
Likes: 62
From: Lake Havasu City, AZ
The least expensive step is to change out the fluid....
Royal Purple is recognized in industry as making the best industrial gear oils. They make a 75w90 synthetic gear oil that you can buy through several national chain autoparts stores....
That would be my first choice.... remember to add 1 bottle of GM (or after market) limited slip ( posi-traction fluid) Add it first to ensure you get the correct dosage)
Others swear by Amsoil which already contains the additive.
Royal Purple is recognized in industry as making the best industrial gear oils. They make a 75w90 synthetic gear oil that you can buy through several national chain autoparts stores....
That would be my first choice.... remember to add 1 bottle of GM (or after market) limited slip ( posi-traction fluid) Add it first to ensure you get the correct dosage)
Others swear by Amsoil which already contains the additive.
