Concensus on best read diff lube please
 

Guys,

I plan to change the rear diff lube. What are you guys using and are you adding the additive? Thanks very much

I just replaced mine with this: https://www.amsoil.com/lander/easypack/index.aspx. lots easier to get into the fill holew.

Whenever there's a question about oil, the Amsoil guys always seem to get in first. I agree that the easy pack is a nice idea, looks easier to use than the pump.

If you want to keep it simple, I recommend Mobil-1 75W-90 LS. Available at your favorite local store. It already has the limited-slip additive in it. Just buy two quarts, drain out the old stuff, pump in the new stuff, done.

Gee Whiz, I waited almost an hour!

Thanks guys

Yeah, I'm a Mobile 1 fan too.

I put mobil 1 also. I had to add GM additive regardless though because of binding around turns. YMMV

Hi tech stuff not necessary. Did my C6 which was chattering. Bought some at Walmart, don't remember the brand. Fixed the chatter and all is good. Had some additive but didn't need it.

if you are just doing normal cruising then most fluids will be fine, if you race or drive the car hard personally I would use high quality stuff

I ended up just ordering redline 75w-90...I think it was a good enough choice

It is...……..I've had the Red Line lube in my differential (and manual transmission) for the last 16 years.

good to know...I am not planning on adding the additive unless i hear noise..
did you ever have to add it?

Nope, used the oil as is...

:cheers:

I did mine a few weeks back.
I used the OEM (AC Delco), with the AC Delco additive. All ok.

Best rear oil ???? NEW

After 20 years, the fluid that came out of the rear looked brand new.....that was nice to see

IMHO, it must have been changed a time or two, before you got the car. From what I understand, GM uses a moly base gear lube, when they initially assemble differentials. That, in turn, makes the original fill of gear oil turn a dark gray. In order to get that gray color out of the diff, usually takes 2-3 oil changes.

I hear ya, but I've owned the car since 98......But you are correct, i did have the diff seal fixed in 02 so it was changed....So I guess its only 16 years old....sorry I forgot....Ahhh, the car has low miles as I am too darn busy with my kids activities and my 79 took much of the racing time.....So, I guess it should be clean and its not a dd.....Still I was happy to see it clean...When I changed the fluid on my 79 which most likely was never changed 25 years later it was like tar...