G80 code is limited slip I dont see it....open.

 

You have an open diff.

G80 is the RPO for the locker.

 

I concur

 

That's an easy remedy that can be solved in one weekend.

 

Well, that's fine that there is no G80 on the Sticker.

But... you have to ask yourself: Am I willing to bet my next paycheck that there is NOT one in that Rear End.

Are all of these Vans maintained in their Pristine Stock State ?

They used to say, "well, you can crawl under there, on the front pass side of the RR end are some numbers..."
Even that could be wrong.

Just sayin', but y'all are probably right , "Chances are..."

Mike

 

Probably needs changing anyway - Pop the cap and take a look - see
Or maybe the Van is not yours yet.

In which case - all bets are off - Good Luck and remember, that great Diff can be added later - no prob.

Mike

 

If you take off the cover you will know right away.

Just for comparison here are pics of a G80 and an open diff side-by-side:

This is the factory Eaton G80 used in our Astro/Safari:

This is what the open diff looks like in my Jeep ZJ project:

 

I wonder: if the left rear wheel is raised an inch from the ground by putting a 2 x 4 about a foot long standing under the axle, then slowly trying to drive off, wouldn't that clearly indicate whether there is a locking or other device in that diffhousing? Seems like a quick and easy check procedure. P

 

I had a limited-slip axle in my first van. It was okay but not life-changing. The specs for the g80 were weird. I didn't fully lock up when I wanted it to and it was unlocked at the weirdest times. If you really want a locking rear axle just put a limited-slip in it. The aftermarket is way better.

 

This is the factory Eaton G80 used in our Astro/Safari:

View attachment 2

I'm not sure, whether I am misreading the picture, but it looks like, there are several g80 set ups, because, what I see in the picture is an LSD, whereas mine looks like this:

, which is the locker. Probably, it Is worth it putting this in a separate thread, since, if I recall correctly, there's beenn a dispute over it, and has never been verified?

 

Here is a link that has diff stamp ID number if that helps
https://www.astrosafari.com/viewtopic.p ... 80#p757497

Isnt that just the back side of the gov loc in that picture?

 

Isnt that just the back side of the gov loc in that picture?

I believe it is not, because, as you see in my picture, the gov lock's cassete is a lot larger, and sguare-ish...

 

I just swapped out an open for a factory G-80 from a junk yard. Cost 108 dollars and a few hours work. At the junk yard I simply turned one wheel, and when the opposite side spun along at the same time it confirmed to me that the door sticker was correct and it did indeed have a G-80. My pick and pull is in KY and they have a gen 3 right next to the one I got also G-80

 

Thank you for all your useful comments!

 

I just swapped out an open for a factory G-80 from a junk yard. Cost 108 dollars and a few hours work. At the junk yard I simply turned one wheel, and when the opposite side spun along at the same time it confirmed to me that the door sticker was correct and it did indeed have a G-80. My pick and pull is in KY and they have a gen 3 right next to the one I got also G-80

Boy, that sounds good , wish I could get down there.

Mike

 

At the junk yard I simply turned one wheel, and when the opposite side spun along at the same time it confirmed to me that the door sticker was correct and it did indeed have a G-80..

I was under the impression that a "G80 locker" didn't engage (spring loaded) until one wheel spun at a certain rate of speed... something like 10mph? No lock on slow turns however.

 

I agree with MMM one tire spins to a speed and then the opposite side locks in and as soon as the main wheel gets traction the opposite releases. It is not designed to burn rubber or race it is designed primarily to regain traction when traction is lost.

 

I agree with the spring loaded locker. (factory) I also agree with the 10 mph spin needed to engage the opposite wheel. I may have just been lucky when I put a rapid spin on the right side and the left side did indeed engage. I had no oil catching system with me at the time and the JY will not allow spilled oil. It was the only test that I could do, since I couldn't pull the cover. Now you have me wanting to go out in the shop and test my theory. To cold today -1 degree, but I will check this out. It may be worth mentioning that no wheels were present at test time just axle. And since I cant be on both sides I simply put a nut on the top lug stud opposite side. When I applied rapid spin the nut went flying. Sold me I did the R&R and was happy when I got home. Turn N Burn is right and an after market can indeed be a superior product.

 

Shhhhhh don't tell my wife oke:

 

At the junk yard I simply turned one wheel, and when the opposite side spun along at the same time it confirmed to me that the door sticker was correct and it did indeed have a G-80..

I was under the impression that a "G80 locker" didn't engage (spring loaded) until one wheel spun at a certain rate of speed... something like 10mph? No lock on slow turns however.

That's what i pointed out earlier: It appears, that there are more than one systems, used in the G80. Mine is the locker, but in Metalvan's picture, it is some sorta LSD. That's why the wheels of tungtide's rear end spin in the same direction, whereas the locker operates, as an open diff, untill a difference in torque, btwn the two wheels, at a predefined speed of spin is applied.

 

Yes, I have seen videos ( we know this, right? ) of the distinct 2 different varieties of these special diffs.

Quite different from what I thought of as a "Locker". Then there is the "Locking Hub" - usually front - thing.

Then, then , then. The Experts will no doubt - clear it up. Gov-Loc, Eaton, OEM, G80, G80 Locker, LSD ( NOT the orange barrel variety ), Open Diff, Closed Diff, etc etc.

Soo many terms, so much time.

"No oil allowed on the ground" or whatever - that is so fun a statement.

Mike

 

Most people refer to the G80 as a Limited Slip differential, not a locker.

 

https://www.eaton.com/us/en-us/catalog/ ... ocker.html

Reliable - Fully automatic engagement
Simple integration - Compatible with existing vehicle stability systems
100% Locking - Equal torque to both wheels

Eaton calls it a locker, that is what I call it as well.

I think maybe some of the confusion could stem from other GM car models that used the G80 code and actually had a limited slip differential in it. :shrug:

"The G80 locking axle provides a greater traction advantage than limited-slip differentials in most situations, while its automatic engagement requires no driver involvement, unlike some competitors' electronic lockers, which require driver activation," said Jeff Luke, executive chief engineer.
"The G80's simplicity, durability and sure-footed grip have been proven with generations of customers, as it has been a staple of the Chevy truck lineup for more than 40 years.

Order options from my 03 Astro:

03 astro rear end options

• AstroWill
• Feb 14, 2019

Other aftermarket traction adders for our vans https://sites.google.com/site/astrosafa ... ferentials

SUBJECT: LOCKING DIFFERENTIAL (G80) LUBRICANT - (SERVICE INFORMATION)
VEHICLES AFFECTED: ALL LIGHT TRUCKS EQUIPPED WITH G80 REAR AXLE ALL YEARS
Some light duty trucks equipped with locking rear axles (G80) may exhibit rear axle chatter, especially when turning a corner from a stop.
This condition of alternate engagement and disengagement of clutches in differential assembly is usually caused by contaminated axle lubricant.
To correct this condition, drain and refill the rear axle with SAE 80W-90 GL5 (P/N 10950849). The use of any additive in locking rear axles (G80) is not recommended. Rear axle additives are designed for use in limited slip differentials which are normally installed in cars. All light duty trucks equipped with RPO G80 make use of a locking differential and the use of additives will delay the engagement of the locking mechanism and may decrease axle life.
VEHICLES/COMPONENTS INVOLVED: ----------------------------- Some light duty trucks equipped with locking rear axles, RPO G80

 

Will, may be worth transfering the whole G80 discussion, in a separate thread, with it's own title, in order somebody looks for it in the future..? :shrug:

 

This is the factory Eaton G80 used in our Astro/Safari:

View attachment 2

I'm not sure, whether I am misreading the picture, but it looks like, there are several g80 set ups, because, what I see in the picture is an LSD, whereas mine looks like this:, which is the locker. Probably, it Is worth it putting this in a separate thread, since, if I recall correctly, there's beenn a dispute over it, and has never been verified?

Your response made me curious because our Astro was a 100% stock soccer mom van with the G80 in the RPO sticker, so I did a little research and found there are different series of G80's.
Some have a small window on one side and large window on the other side, some have 2 large windows.
Each series has slightly different shoulder shape, but all are more squared off than the bell in an open diff carrier.
In the pic of ours, the carrier is turned around to the small window side, but you can see the bolt heads in the shoulders.
LSD's have springs visible in every pic I could find, ours doesn't have springs.