clunky rear end

[glennkrick]

Has any one solved the clunk in the rear end on the C-6 yet?
I live in Minnesota and in the cold weather the rear end seems to bind and snap when turning sharp at low speeds. The dealer has replaced the rear end fluid but there is no improvement. This was never a problem on my previous Vetts. It's my understanding this is a different rear end than the C-5?
I suspect it's a cheaper no slip setup than the old one.
Glenn krick 612 964 6777
glennkrick@gmail.com

[Dad]

Check your rear axel nuts and replace them if they are loose. Mine have been replaced for that very reason and they were very loose. Crap engineering to smash the nut hexagon to deform the thread; which also deforms the face and doesn’t allow good face contact at torque.

There is a TSB out on the issue.

[glennkrick]

Thanks for the help. Are you referring to the lug nuts?
Glenn

[Tuna]

If the clunk goes away as the car warms up, then the rear differential probably needs service to replace the fluid with new stuff.

I have not experienced any rear end noise with my '08 but my '06 has had to have the rear end fluid replaced twice - haven't had any clunking noises in a while now.

[Dad]

Thanks for the help. Are you referring to the lug nuts?

Glenn

No, I'm talking about part number 10257766 drive shaft/axel nut (made in India). One per axel. It can snap so loud that you can hear it outside the car. I was on the verg of changing my CV joints it was so bad. Then my local Chervrolet tech said to check the nuts first after the fluid change did no good.

Side note, the picture in the manual shows the punch locking the brake disc for a left hand thread, not ture. Just a cheap way to reuse illustration number 174557 on page N-90.

[NORTY]

The rear axle nut looks like this~

[c4c5specialist]

HI there,
POST the differential fluid that was used at the dealer.

Allthebest, c4c5

[Dad]

THIS is what was on their service sheet, Dextron LS Gear Oil 75W-90 (GM part part #88862624). I have to think that they might have changed it because the parts man told me they had to buy a case and most likely would never use it up. Think he may have been pulling my leg. On the other hand at the cost of it they may never have put it in, just drove it around the parking lot in figure 8s.

Why did you want that information? Does this particular fluid have known failures? Is there a later fluid out? If so please enlighten the group.

[c4c5specialist]

Hi there,
That is the correct fluid and if they dont have it in stock, I would be worried.

This fluid is the absolute BEST FOR C5 and C6 differentials.

Allthebest, c4c5