What's new
CK5
Register an account today to become a member! Once signed in, you'll be able to participate on this site by adding your own topics and posts, as well as connect with other members.

G80 Discussion & Tech!

Avery4jc

Avery4jc

1 ton status
GMOTM Winner
Joined
Oct 24, 2005
Posts
10,790
Reaction score
164
Location
Fresno, Ca.
EDIT: This started out as a help for a discussion but its turned into a good G80 Tech thread so I changed the title for future people searching for G80 information...


Ok so over on GMFS there is a guy that started a thread on driving in the snow w/ lockers... throughout the entire thread he kept saying he has a locker (he has what looks to be a '05-'06 1/2 ton CCSB Chevy) and then someone asked him what locker he had and he said G80...
I made the stupid decision of laughing about it b/c as far as I was concerned a G80 is a limited slip... upon googling it appears its been called both a limited slip and a locker...
So who is right?

He posted this as evidence...
http://www.eaton.com/EatonCom/Markets/Automotive/TorqueControls/index.htm
 
Last edited:
Avery4jc said:
Ok so over on GMFS there is a guy that started a thread on driving in the snow w/ lockers... throughout the entire thread he kept saying he has a locker (he has what looks to be a '05-'06 1/2 ton CCSB Chevy) and then someone asked him what locker he had and he said G80...
I made the stupid decision of laughing about it b/c as far as I was concerned a G80 is a limited slip... upon googling it appears its been called both a limited slip and a locker...
So who is right?

He posted this as evidence...
http://www.eaton.com/EatonCom/Markets/Automotive/TorqueControls/index.htm
Click to expand...

True locker with clutches to soften the locking AFAIK...although a decidedly weak one.

I blew mine out...on snow and ice :doah:
 
The one that was in my 97 2500HD acted like a locker once it was locked. I had some junk tires and was having some fun in a parking lot, and as long as you didn't shift into reverse/nuetral, it would stay locked. Take a sharp turn and the tires would chirp, and the whole truck would shutter. Once you backed up, basically taking the tension off the rear, it would unlock. So, in a sense it is a locker, not a limited slip. But this is on a full floater, never had one in anything else, so can't comment aboot them.
 
bummer... I wonder why I've always thought of it as a limited slip...
maybe b/c I've read about the clutches like Jon said..
I have to go admit my defeat :)
 
G80 is a generic GM RPO.

G80 has been used for the Eaton Gov-Lock, Eaton clutch limited slip, Auburns, GM Corporate, and a couple of other styles.

I don't know the real deal on teh manufacture anymore, I've heard that GM or AAM or someone is making their own style of "gov-lock", but it's the only one of the above that is somewhat of a locker, even though it has clutches.

For the most part, G80 indicates a Gov-lock on GM trucks from the first the Gov-lock was used. I really don't know if GM used the G80 RPO on trucks that did NOT get the Gov-Lock, but there were actual limited slips (and lockers in the 5/4 ton CUCV, right guys?) used in the trucks for a few years.

In a NEW truck, I doubt G80 means anything other than Gov-Lock, it saves money for GM to use one piece in everything, instead of having 3 or 4 different traction aids available.

Oh, and if you need proof for those guys, check any Buick GN, Olds Cutlass, or Monte Carlo RPO list online, as none of them had gov-locks. They were all RPO G80, and were clutch style limited slips, whether 7.5" or 8.5" axles.
 
I just found that on Wikipedia... (about G80 being pretty generic)...

I guess I'll go toss that in and add fuel to the fire... thanks Dorian :)
 
Thats interesting I always assumed the G80 was only for the gov-lock, not LSD's too. Didnt GM introduce an electric one recently? I know on my 01 tahoe it had the rpo G80 and it was gov-lock undoubtly, I rebuilt the rear end and took that thing out and stared at it for a while...
 
E-locker, isn't that what the H whatevers (H2?) are using? If it's in a variety of vehicles, they may indeed use a different RPO, since they are so specific in how they work.

It has struck me as odd that G80 was so generic, it doesn't help the dealer determine what they will be working on, which I would think a major advantage of having it on the sticker.

There ARE a couple of other differential traction aid RPO's, but only like one or two IIRC, and I've never run into them on an RPO tag.
 
What do CUCV's like the M1008 and M1028 list as the RPO code for the detroit?
 
That's a good question. Lemme go see if mine even has a glove box build sheet...


For the record the Grenade Lock is a limited slip. Lift one tire and watch what happens...the airborne tire keeps spinning and the tire with traction stops moving. Not exactly locker behavior.

Wonder what the build sheet code was back in the pre-73 trucks when they put Detroits in some of the Eaton rear ends?
 
Mine has no build sheet in the glovebox. Not sure if any of them did but I know mine ended up with some civilian take off parts on it when it was "rebuilt" last year. I'll ask on SteelSoldiers since I'm curious now.
 
truck072.jpg

There's one guy's tag. I bet the locker was part of the military package.
 
AJMBLAZER said:
For the record the Grenade Lock is a limited slip. Lift one tire and watch what happens...the airborne tire keeps spinning and the tire with traction stops moving. Not exactly locker behavior.
Click to expand...

Yours is broken. :)

More than approx. 100RPM difference in axle speed, under 25MPH vehicle speed, the differential WILL lock if working correctly in the situation you describe.

In a properly operating gov-lock axle, lift the axle and SLOWLY rotate one tire and as long as the brakes aren't dragging, the other tire will rotate in the opposite direction. Jerk the same wheel hard in one direction and you will lock the axle.

Properly operating gov-lock is actually pretty fun to drive. When they go bad, not so much.
 
yea the gov lock is true a locker in the sense that it locks up 100% completely. Towards the end before I ditched mine, it wouldnt always lock up and when it did it was not nice. Its a great concept and it works good, to bad its not tough enough to handle anything more than a stocker.
 
The 14 bolt gov lock is considerably stronger than the 10 bolt version. My GMC will psin the one tire once around then lock in, and spin them both equally afterwards.
 
what I want to do is spend some time under the truck and find a way to use a switch to activate my electric locker inder my 07

I had heard of it being done or talked about by someone I know but I dont know if he ever got it done or if he had just tested the idea.

mine works pretty well and has impressed me more than once!
 
supersize75k5 said:
what I want to do is spend some time under the truck and find a way to use a switch to activate my electric locker inder my 07

I had heard of it being done or talked about by someone I know but I dont know if he ever got it done or if he had just tested the idea.

mine works pretty well and has impressed me more than once!
Click to expand...

What do they put in the new trucks? Or is it an in-house built unit?
 
You must log in or register to reply here.

Latest Posts

Top Bottom