I got 1989 chevy 2500 it has RPO code G80. Is it a limited slip,posi traction, or a Locker? If it is one of those what is the difference between them?
What gear oil should I be using?
What gear oil should I be using?
You are using an out of date browser. It may not display this or other websites correctly.
You should upgrade or use an alternative browser.
You should upgrade or use an alternative browser.
Chevy G80 is it positrac,limited slip, or Locker?
- Thread starter goodoleboy
- Start date
- Status
- Not open for further replies.
Positraction was GM's name for a limited slip differential. The old G80's were traditional eaton limited slips, but I have read that has changed on the newer vehicles. A traditional limited slip differential uses clutches that release a wheel once a certain torque has been reached. A locker is essentially a ratchet, that never allows either wheel to spin slower than the ring gear in the rear end......but will allow a wheel to spin faster than the ring gear during cornering.
It's all of the above. The G80 used in GM brand trucks combines the clutch plates of a traditional Limited Slip differential with the positive engagement of the traditional mechanical locker.
It does this by using a mechanical flyweight and a governor inside the differential, hence the "Gov Lok."
Point your browser to the following Eaton URL for a detailed description. You'll probably want a broadband connection to see the movie on how the parts go together and work, it's almost 3 MB.
http://www.traction.eaton.com/prod2.htm
http://www.traction.eaton.com/images/G80.mpg
It does this by using a mechanical flyweight and a governor inside the differential, hence the "Gov Lok."
Point your browser to the following Eaton URL for a detailed description. You'll probably want a broadband connection to see the movie on how the parts go together and work, it's almost 3 MB.
http://www.traction.eaton.com/prod2.htm
http://www.traction.eaton.com/images/G80.mpg
The Eaton Lockerquote:
The Eaton Locker…When the Three Most Important Words Are Traction, Traction, Traction
You ever had your drive wheel slip off the road and into some mud? Or maybe snow or ice? Makes it hard to keep it going in a straight line, doesn't it? Traction just disappears…
What about a boat ramp? Ever been in a situation where one side of the ramp is all wet and slippery while the other side is dry as a bone? With an open differential, all you'll do is spin the wheels. And, even 4-wheel drive doesn't do much good in that situation.
Well - surprise - there's a solution. The Locker. The Eaton G80 Locking Rear Differential. This automatic unit, available for rear drive and 4-wheel drive vehicles, makes traction problems a thing of the past. The Locker makes towing large boats and campers a breeze.
It gives you the freedom to wander far from the beaten path in search of the perfect fishing hole, campsite or picnic area. It delivers traction and inspires confidence even in the nastiest off-road terrain.
A Quick Look At How It Works...
We'll start by pointing out that the Locker is a speed sensitive design. That is, it reacts to wheel slip by sensing when one wheel is spinning substantially faster than the other.
So, when you're cruising along on clean dry pavement, the locker operates like any regular open differential.
But, as soon as wheel slip happens, going forward or reverse, the locker immediately kicks in. Here's how.
The differential is set up with a flyweight governor that responds to differences in wheel speeds, and disc packs that are mounted between the side gear and the case.
Whenever one wheel is spinning substantially faster than the other, the governor spins rapidly, causing the flyweight to open. That flyweight then catches on a latching bracket and the lockup process begins.
During lockup, a self-energized clutch system causes a cam plate to ramp against a side gear. This ramping action compresses those disc packs mentioned earlier. The ramping continues until both axles - and therefore both wheels - are spinning at the same speed. This is full lock, and it prevents any further wheel slip. (Note: Axle lockup can only occur at speeds below 20 mph.)
The entire lockup process takes about a split second, and is virtually unnoticeable by the average driver. When both wheels regain traction, unlocking occurs and things go back to normal.
Want to see it work from the inside? Click here
Where can I buy a mechanical locker?
The Eaton Locker is option code G80 Locking Differential on GM light trucks and SUV's. Go to Chevrolet, GMC, Cadillac or Oldsmobile websites for more information.
So, what could make it better?
How about giving the driver complete control of when and what gets locked? The ability to lock the front axle, the rear axle or both axles with the touch of a button? OK, now you're talking ELocker™ Differential, the Electronic Locking front and/or rear differential…
Yeah right! A friend of mine has a 95 K2500 (6.5TD) and his locker is anything but unnoticable. It SLAMS when it locks, which can suddenly kick the rear end of the truck out around a wet corner. I'll take Eaton's regular clutch-type limited slip any day...quote:
Originally posted by Mike:
The entire lockup process takes about a split second, and is virtually unnoticeable by the average driver. When both wheels regain traction, unlocking occurs and things go back to normal.
It seems about 1/4 of truck G80's have harsh engagement. It's most noticeable if one wheel in on bare pavement and the other wheel is on glare ice.
Since both wheels lock to provide equal torque, an empty truck will step out to one side, just like a Detroit Locker rear end. Remember the G80 is activated based on wheel speed difference, not based on input torque.
The worst thing you can do to a truck G80 is put one foot on the brake and floor the gas: the flyweight governor assembly can actually explode. The G80 has been called the "Grenade 80" due to that reason.
If you're going to horse around, use a limited slip. The large "S" spring biases the left and right clutch packs and is very tolerant of abuse. The more input torque you apply, the stronger the clutch plates engage.
Since both wheels lock to provide equal torque, an empty truck will step out to one side, just like a Detroit Locker rear end. Remember the G80 is activated based on wheel speed difference, not based on input torque.
The worst thing you can do to a truck G80 is put one foot on the brake and floor the gas: the flyweight governor assembly can actually explode. The G80 has been called the "Grenade 80" due to that reason.
If you're going to horse around, use a limited slip. The large "S" spring biases the left and right clutch packs and is very tolerant of abuse. The more input torque you apply, the stronger the clutch plates engage.
G80 is simply GMs option code for something above an open diff. yes it is a gov lok in the trucks but in the cars like the Caprice/Impala it is an Auburn clutch style limited slip. Like others have cautioned don't overrev that thing the gov lok can and does suddely lock both wheels when a certain rpm differential is reached think of it like your foot slipping off the clutch with the engine at speed no slip just BANG engaged. The chances of something snapping are far too good for comfort.
The poster goodoleboy has an '89 Chevy 2500, the LD or HD 3/4 ton pickup RPO G80 is the flyweight governnor with clutch plates.
The only difference between the LD and HD 2500 axle is one is a semi-floating and the 2500HD is a "true" HD full-floating design.
As far as gear oil to use, the owner manual is a good starting point. Some synthetic gear oils don't have the proper friction modifiers for proper clutch plate operation.
If in doubt, make sure the gear oil states "for limited slip service."
The only difference between the LD and HD 2500 axle is one is a semi-floating and the 2500HD is a "true" HD full-floating design.
As far as gear oil to use, the owner manual is a good starting point. Some synthetic gear oils don't have the proper friction modifiers for proper clutch plate operation.
If in doubt, make sure the gear oil states "for limited slip service."
- Status
- Not open for further replies.
Similar threads
- Replies
- 26
- Views
- 2K
- Replies
- 1
- Views
- 173
- Replies
- 28
- Views
- 2K
- Replies
- 3
- Views
- 1K
