Clunking differential when cold

Reply Subscribe

Thread Tools

Search this Thread

Sep 17, 2008 | 11:01 PM

VetteLes

Thread Starter

Racer

Joined: Nov 2005

Posts: 315

Likes: 0

Clunking differential when cold

Until I've driven a couple of miles, I hear a clunking in my differential when I back up or just pull off from a stop. After warm up, this condition stops. Anyone else with this situation? Fix?

Sep 17, 2008 | 11:03 PM

danl72

Race Director

Joined: Apr 2008

Posts: 17,373

Likes: 6

From: Chatsworth California

You should go to the dealer and have them change the fluid.

Sep 17, 2008 | 11:11 PM

VetteLes

Thread Starter

Racer

Joined: Nov 2005

Posts: 315

Likes: 0

Quote:

Originally Posted by danl72

You should go to the dealer and have them change the fluid.

Thanks,

Thought I read something about a technical bulletin for this. Just couldn't recall if it was for my C5 or C6. Do you know if one has been issued?

Les

Sep 18, 2008 | 03:56 AM

ZO6 Fan

Pro

Joined: Mar 2007

Posts: 585

Likes: 0

From: Coral Springs Florida

Quote:

Originally Posted by danl72

You should go to the dealer and have them change the fluid.

They also put in an additive to help. I believe it has to do w/ the differential clutch packs being too tight. I have to take mine back again for a second time

Sep 18, 2008 | 02:14 PM

99ssconv

Instructor

Joined: Jan 2006

Posts: 246

Likes: 4

From: Denton County Texas

Important: DO NOT add any limited-slip additive (friction modifier). With this new fluid (Dexron LS Gear Oil 75W-90) it is no longer required to add friction modifier. If friction modifier is added, it will cause the fluid to lose some of it's friction reducing properties as well as reducing seal life.

Fill the differential with the new DEXRON® LS gear oil, P/N 88862624 (Canadian P/N 88862625).

Sep 22, 2008 | 09:34 PM

VetteLes

Thread Starter

Racer

Joined: Nov 2005

Posts: 315

Likes: 0

Thanks for all the advise. I spoke with my Service Manager and he told me to bring it in and get the latest fluid. He also said that in some cases, it requires two fluid changes to get all the noise out. He'll change it, let me drive 10 miles and then if necessary change it again. Nice to have a service manager that works with you.

Sep 23, 2008 | 12:16 AM

*FAÇADE*

PHOTOSHOP SPECIALIST

Joined: Aug 2007

Posts: 16,433

Likes: 40

St. Jude Donor '07-'08-'09-'10-'11-'12-'13-'14-'15-'16

Quote:

Originally Posted by VetteLes

Thanks,

Thought I read something about a technical bulletin for this. Just couldn't recall if it was for my C5 or C6. Do you know if one has been issued?

Les

Below is the updated TSB on this condition that utilizes the new DEXRON® LS Gear Oil 75W-90, P/N 88862624.

Last edited by *FAÇADE*; Nov 30, 2008 at 12:51 PM.

Sep 23, 2008 | 01:51 AM

LS WON

Team Owner

Joined: Dec 2002

Posts: 32,074

Likes: 296

From: San Francisco CA

Quote:

Originally Posted by 99ssconv

Is this Dexron LS fluid for the rear end a synthetic gear oil? Why not just switch to redline synthetic rear diff. fluid then you don't need to add any friction modifier. You could also use Redline for the auto trans and manual trans. Why not use the Redline instead? Isn't it superior to any tranny oils or rear diffs oils GM is selling?