G80 Locking Dif

djv1951 · November 8, 2006

Can anyone tell me how the G80 locking dif. works? While on a hunting trip this year in my 2004, 2500hd 4X4, I was in 2 wheel drive and the left rear wheel started to spin in the mud but the right wheel did nothing. Should have it locked up and at least the right wheel started to spin also?

Rookie · November 8, 2006

It will noly engauge below a certian speed. Go to this web site it should show you all you want to know

eaton

ZZebes · November 9, 2006

The G80 is a really expensive paper weight, I have cooked 2 of them in just over 20,000 miles. the way it works is that once there is a 100 RPM difference between the wheels it trys to kick in but not if you are going faster than 20 mph

Go get a real locker like an Detroit Locker of an E-Locker

Paulie G · November 9, 2006

So..............If you under 20mph and one wheel is spinning, the other wheel locks up in sink with the spinning on.

My question is...........Does it stay locked up until 20mph or does it disengage when both wheels start spinning the same. Do you see where I'm going with this?

Up till 20mph.......does the locker continuously engage and disengage if one tire is going to have poor traction for a distance? (up a driveway under 20mph for instance)

hard to put into words but do you catch my drift?

Butch 02 Denali · November 9, 2006

From their website:

Principles of Operation

¨ Wheel speed difference (left to right) in excess of 100 RPM will cause a flyweight mechanism to open and catch a latching bracket.

¨ The stopped flyweight will trigger a self-energizing clutch system, which results in the cam plate ramping against a side gear.

¨ Ramping increases until both axles turn at the same speed (full lock), which prevents further wheel slip.

¨ At speeds above 20MPH, the latching bracket swings away from the governor and prevents lockup from occurring.

Technical Specifications

¨ Automatic locking takes place within a fraction of a second, so smoothly that it is unnoticed by the average driver.

¨ Unlocking occurs automatically, once the need for improved traction is gone, and is unnoticeable to the average driver.

They kind of say that as soon as both wheels get to the same speed it disengages, but that would mean it would continually be engaging and disengaging if traction was limited.

srlbotanical · November 9, 2006

I've had a blown G80 for a while.

I don't have the cash for a new truetrac right now, so for the time being I am just keeping an eye on it. The other night I had to open the Differential to replace my axle seals. I took a few pictures of the G80 to show what went wrong with the locking mechanism.

When one wheel spins faster then the other, a set of flyweights swing out catch on a governor plate. The arrow is pointing to the flyweights.

When you go over about 20 MPH the Governor plate swings out and lets go of the flyweight so the wheels unlock.

The way the G80 works is really kind of cool, but if you do any kind of off roading or if you incounter wheel spin on a regular basis, than in my opionion its just a matter of time befor it fails. The problem is that all the force of the wheels being locked together is held by a small toothed pin that the flyweights are attached to. Sooner or later, if you encounter enough force (such as an icy wheel-spin that catches suddenly,) these teeth shear off the pin.

In the picture below, the arrow is pointing to the flyweight pin. You can see the teeth on the bottom of the pin have been sheered off.

Once that happens, you basically have an open carrier, and its the Right-wheel-peel for you.

Some people have had thier G80 actually grenade and blow out the spider gears and all.

Hope that helps.

Steve

pwall · November 9, 2006

Interesting thread.

Without having to take the diff cover off, is there an easy way to tell if the locker is gone south ?

srlbotanical · November 10, 2006

Interesting thread.
Without having to take the diff cover off, is there an easy way to tell if the locker is gone south ?

<{POST_SNAPBACK}>

Well, I started noticing that my right wheel was spinning a lot more then it used to. we have a pole barn on the back of our property and you have to go up and down a few steep grass slopes. When my g80 was working I could just creep up the slope, one wheel would start to slip a little and the other would engage right away. Now, the right wheel starts to loose traction and the left never jumps in to help.

That's when I had the feeling that my g80 had gone south. When I opened up the pumpkin to change out the gear oil it was nice a glittery and the teeth on the flyweight pin were sheared off...

Steve

lagrange151 · November 10, 2006

The G80 or Gov-Lock is known in the 4x4 community as the "Gov-Bomb"

Paulie G · November 10, 2006

If even the slightest situation occurs, I have to lock it in or else I'm going nowhere.

I always thought it was the weight of the 8.1 up front and the empty long box behind the crewcab not allowing any traction.

Maybe my G80 is shot

Nice post srlbotanical!

FindingRhino · November 14, 2006

OK Now you've got me paranoid my G80 is going to blow up as I drive up my steep snow covered driveway this winter.

Does it work in Reverse?????

srlbotanical · November 15, 2006

OK Now you've got me paranoid my G80 is going to blow up as I drive up my steep snow covered driveway this winter.

Does it work in Reverse?????

<{POST_SNAPBACK}>

I can't see how it would work in reverse. The flyweights only catch in one direction and it seems to me that they can't catch if spun the oposit direction, I can't see anything on the governor plate that they could catch on in reverse. So, my money would be on NO.

Someone here will correct me if I am wrong...