johnsub

Just had dealer change my rearend fluid. It has clunked for 4 years. I ordered Amsoil gear oil and dealer put it in. Solved the problem immediately! Plus I got to go to the Wal-Mart parking lot and do some figure eights! People probably thought I was nuts. Anyhow no more clunking. Car is quiet as it should be. This does solve the problem.

cthusker

.... did mine 3 years ago and not another clunk!

not08crmanymore

Had mine done COUPLE OF MONTHS AGO.Quiet as a mouse when I put it away for the winter.It's wierd not hearing anything!

wolfpack06

Did mine on a military base with a lift... nice setup. I was suprised I wasn't flagged for suspicious activity doing figure 8's in parking lot right after

bosco 08

My 08 started making noise about three months ago [8500 miles] i finally took it to the dealer with 6 days left on my warranty. They replaced the fluid with the new part # and 45 minutes later i'm back on the road. No noise.

keyplyr

Next time buy one that doesn't clunk

Vette5.5

So how's your posi diff clutch lock up action now. Had a noisy diff in a Z28 Camaro year's ago so put the recommended GM additive in. Most of the posi clutch lock up didn't work shortly after. Not making that mistake again in the Vette, and just live with the noise around turn's.

mike100

I had them do mine on the recommended tsb for it at 10k miles. Figured it was a good excuse to dump the old fluid to get the metal bits out from break-in and solve the posi-clutch plate noise at the same time.

TINCANMAN

i just had my 05 diff fluid changed this past sping.i was told gm does not want any posi lock additives put in even though the manual recommends it

cclive

With the new Dexron LS fluid, no friction modifiers are needed.

Always Red Dave

Yes did mine in july and yes It solves the problem immediatelyand yes I also got to do figure eights !

traindude

Had the rear diff fliud changed on my 07 a few years ago, and no more clunking since then.

Swampthang

I did mine a few weeks ago and it hasn't clunked since.

JRS 94

diff fluid, alignment, and leaking waterpump at 12,000 miles. Interesting...

C66 Racing

Johnsub - thanks for posting this.

For the C6, I would recommend this for those considering AMSOIL:
AMSOIL Severe Gear Extreme Pressure Synthetic 75w90 (Product Code SVGQT)
AMSOIL Slip-Lock Differential Additive (Product Code ADATB)
AMSOIL Hand Pump (Product Code G2039)
Note: I'd remove the tip off the hand pump fill line - not needed and may come off where you don't want it to.

Also note that the Severe Gear 75w90 comes with friction modifier in it and for the C5, adding extra additive is not needed to prevent diff chatter. I run this fluid in my SCCA T1 02 Z06 with no extra additive and have no diff chatter. But, the C6 diff has different characteristics and for the C6, I'd recommend getting a bottle of the Slip Lock additive and at least putting half (2 oz) of the bottle in with the fluid change.

For anyone desiring to try this fluid, more than happy to get it to forum members at dealer wholesale, about 25% below retail, via the AMSOIL Preferred Customer Program. Drop me a PM if interested.