G80 staying locked after new spider install

[wsteele]

I think @exp500 and @swathdiver are right.

I was just reading about the G80 on another forum. There was a post that had an excerpt from a GM bulletin that specifically calls out limited slip additive as the culprit in bad acting Eaton Locking diffs. The bulletin recommends a complete flush and replacement only with the recommended synthetic gear lube.

 

[phatz_hatz]

I think @exp500 and @swathdiver are right.

I was just reading about the G80 on another forum. There was a post that had an excerpt from a GM bulletin that specifically calls out limited slip additive as the culprit in bad acting Eaton Locking diffs. The bulletin recommends a complete flush and replacement only with the recommended synthetic gear lube.

now should i just use 75w90 acdelco synthetic and just open up the diff cover to flush it out

 

[OR VietVet]

Use a degreaser or brake clean to clean it all out. Hell even carb cleaner will work. Clean it all out and blow it all dry. No additive.

 

[wsteele]

now should i just use 75w90 acdelco synthetic and just open up the diff cover to flush it out

I agree with Ron. In that piece, they said Eaton and GM recommended a complete flush and cleaning to remove any traces of the LS additive and then just the Delco Synthetic lube. They didn't specify weight as some call for the 80W90 and others 75W90. I suspect either would be fine. Your owners manual will call it out though.

 

[exp500]

Usually the additive makes chatter, rather than fully not unlocking. As I stated before, I think someone else was in it and may have shimmed it for more offroad lock. Something that shouldn't be done to G80. Hard to tell what some folks are thinking while they turn wrenches.
I've said many times before-"Some Poeple Shouldn't Have Tools".
My guess is about 350-450 at the yard for replacement. Hub to hub.

 

[phatz_hatz]

Usually the additive makes chatter, rather than fully not unlocking. As I stated before, I think someone else was in it and may have shimmed it for more offroad lock. Something that shouldn't be done to G80. Hard to tell what some folks are thinking while they turn wrenches.
I've said many times before-"Some Poeple Shouldn't Have Tools".
My guess is about 350-450 at the yard for replacement. Hub to hub.

no one Deff didn’t shim it for off road use it was fine before and just bombed on me so i figure I’d just do it myself considering i looked up enough on it before i took it apart put everything back together properly. I’m an ASE very mechanic just don’t get it might be the mechanism it self still yet to change the fluid and just drivin her diligently

 

[exp500]

Glad to hear It's in good hands. Keep us updated on findings.

 

[thompsoj22]

Your govlock is engaged somehow, pull the cover and spin the diff and see what is going wrong, Youll be on the road in a couple hours for the cost of some gear oil. The additive is a "friction modifier" not a locking mechanism and my opinion the additve is not the problem> so you have the EATON M locker?

 

[phatz_hatz]

well its been raining cats and dogs for past couple days havent had the oppurntunity to open the plate up been driving her easy, hopefully weather clears up so i can get in there

 

[phatz_hatz]

Your govlock is engaged somehow, pull the cover and spin the diff and see what is going wrong, Youll be on the road in a couple hours for the cost of some gear oil. The additive is a "friction modifier" not a locking mechanism and my opinion the additve is not the problem> so you have the EATON M locker?

im not sure if its the eaton but it is the G80 M locker which im sure is made by eaton i also suspect that the fluid is not the culprit and it is soemthing more i just need to open it up and see what it is