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.

Gov lock???

stallion85

stallion85

1/2 ton status
Joined
Jul 11, 2003
Posts
3,657
Reaction score
0
Location
Cedar City, UT
Do gov locks recquire any maintanance? ie; special lube added to diff fluid or clutch pack rebuild kits? I am not quite sure how they work? It is basically a posi trac right? Any input is encouraged, besides you know your gov lock is a piece of !!!! right? You need a locker, dude. I know, I know. For right now the locker is going in the front if there is one going in. /forums/images/graemlins/thumb.gif
 
GM told me that unless your getting chatter on the streets then don't need to add lube.
They have clutches in them that wear.
You can buy rebuild kits for them through eaton that I read before for the 14 bolt.
 
i haven't put and "special lube" in mine. it has some type of clutch packs in it but i dont know what for, it might be the actual locking part of it. i know some who have put the LSD additive in theirs and it doesn't locks.

BTW i like mine, but am waiting for it to blow so i have an excuse to put a 14bff with detroit in it /forums/images/graemlins/waytogo.gif
 
I read somewhere, that the "special lube" is actually for making the clutches slip more than grab too much, something along the lines of if they grab too much, they wear out faster.

But also with the Gov-Locs, your not supposed to use the additive in them, only the limited slip spring and clutch diffs.
 
[ QUOTE ]
BTW i like mine, but am waiting for it to blow so i have an excuse to put a 14bff with detroit in it /forums/images/graemlins/waytogo.gif

[/ QUOTE ]

Good luck, i beat the snot out of my 14 bolt SF for two years and never managed to break it. Even had the 38.5s on it for a while.
 
Just to see what makes 'em work, I just disassembled the old Gov-Loc from my S-Jimmy. It's actually a pretty slick contraption! A fine-toothed gear on one end of the diff will start a small, weighted governor spinning if the 2 axles start to rotate at different speeds. The governor is spring loaded, so that it won't engage the posi until the speed difference between the 2 axles is approximately 100 RPM (so you don't fight the posi in normal cornering). Once that RPM is reached, a pair of cogs swings outward and engage against another governor-type device (one of the cogs works for forward motion, the other for reverse). This stops the first governor from spinning, which stops the fine-toothed gear on the end of the shaft from spinning. The fine-toothed gear has a wave-shaped back, which normally fits into another wave shaped section on the side gear. When the governor forces the fine-toothed gear to stop rotating, the two wave-shaped sections of the gears start sliding against each other, which forces the side gear to move towards the center of the diff. As it moves, it applies force to the clutch packs, connecting the two side gears together via friction.

Now, remember the 2nd governor-type device? It is also spring loaded, and once the wheels are spinning at about 30 MPH, it swings out of the way and disables the ability of the first governor to lock against it.

So in normal driving, there is nearly zero preload on the clutch packs (there's a small wave washer that applies just enough pressure to keep the clutches from rattling around when the posi isn't engaged), which means your diff behaves as if it were open.

When a wheel starts slipping (below 30 MPH)the posi engages quickly and firmly, providing drive to both wheels.

Over 30 MPH, the posi can't engage, so it won't create any driving quirks at speed.

It's a pretty damn nifty piece of engineering! /forums/images/graemlins/thumb.gif But the trick to making one live is to be easy on the throttle. Doing stuff like full-throttle bursts from a standstill in the mud, or on ice/snow, will cause a tremendous shock load as the clutches are slammed home and everything locks together. That's when gov-loc-go-boom! /forums/images/graemlins/wink.gif

All of the other clutch type posis that I can think of work very differently. They typically have a couple of mongo springs inside, that pre-load the clutches against the side gears. This means that the clutch packs are always trying to keep the axles from rotating at different speeds. As you go around a corner, the traction of the tires must overcome the friction of the clutch packs before the diff will actually allow differentiation. This is the type of posi that will be most likely to chatter. Posi additives modify the friction coefficient of the clutches so that they can operate more smoothly when cornering. Since the gov-loc doesn't engage the clutches until they're needed, it doesn't need the additive. /forums/images/graemlins/thumb.gif
 
That's cool how it works only under 30 mph, but I wish it didn't take the 100 rpm difference to make it work. Do the gov-locks in a 14 FF work the same way? They look a lot different than the ones in a 12 bolt.

From what I have read the gov'lock does not need any additive, BUT:

My 14 bolt FF has a gov-lock and I changed the oil in it and then it wouldn't lock in, it just made a horrible grinding noise. I asked both of the local 4x4 shops around here if I had to use any additive, they both said yes. They sold me 2 tubes of Dana "friction modifier" and it works great after adding them. I know of a couple other people that had the same thing.
 
taken directly from HERE

[ QUOTE ]
Availability

¨ Standard Equipment on Dual Wheel 3500 Series trucks.

¨ Optional Equipment (G80 Order Code) on all GM two-wheel and four-wheel drive light trucks and sport utilities.
Benefits

¨ Improved traction differentiates the vehicle relative to other rear wheel and four-wheel drive vehicles on the market.

¨ Functions as a limited slip differential during normal driving conditions; provides full axle lock when needed.

¨ Maintenance free; requires no lube additives.

¨ Enhanced towing and off-road performance.

¨ Patented carbon friction disc technology enhances performance and durability while reducing warranty claims.
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.

¨ Compatible with anti-lock brake systems.

[/ QUOTE ]
 
Wow, thanks guys, lots of cool info! I will just leave it as is just to be safe. I have had no problems so far /forums/images/graemlins/thumb.gif Just curious??
 
Anyone got a picture of a gove lock??? I got an extra 10 bolt and am not sure what is in it... /forums/images/graemlins/confused.gif
 
14786Diffs_005-med.jpg


14786Diffs_004.jpg
 
That's a great pic of a 14-bolt Gov-Loc, but the 10-bolt version looks nothing like that. /forums/images/graemlins/blush.gif

There was a link above that takes you to the Eaton website, and a picture of a 10-bolt version. /forums/images/graemlins/thumb.gif
 
You must log in or register to reply here.

Latest Posts

Top Bottom