99 Silverado - Locking Diff ? & Fluid ?

Fairly sure the Mobil-1 includes the additive, but it's also not needed with the G80. Not sure about the vent, I've heard the same thing, and seen posts about it on web forums. There's a good one on the forum at

in the 1500 forum, I think.

You don't need any additive in the rear diff.

Yes, there is an updated white vent for use with synthetic fluid. If you don't change the vent, the synthetic fluid reacts with the original black vent and it will often loosen up and fall out of the diff.

Ian

Yup,

The G80 is the "Eaton Mechanical Locker". It's engaged by a small flywheel that spins when axle speeds differ. It engages a ramp that locks to the two axles together. (rather violently, in my opinion).

-marc

Yeah, I think they're definitely good for stock applications.

I'm into the high performance drag-race stuff, where they're not the best choice...

I've had three trucks over the years with them and this new one here _definitely_ works better than any of those older ones. I wonder if any changes were made? The truck is also all wheel drive, so that definitely helps some.

-marc

Check out

and

The Eaton page has animation to show how the G80 works, They also offer a clutch unit. Tractech link owns Detroit locker, they also offer other designs.. some based on the old Spicer power-lock

JJ

Ian,

I was going to stop by the Chevy dealer this week and see about this replacement vent tube that is mentioned in this thread. I put synthetic gear oil in mine as of this past summer and would like to replace the tube before it fails. Is there anything that I need to tell the parts guys to get this updated tube? Ask for the white colored tube? Or do they just come that way now?

Thanks Brian

They will know which one to give you. It is white collared and the swivelling section of it is metal.

Ian

Thanks Ian, I'll stop by and get one this week.

Brian