Positraction

[cbrown4390]

Is positrac covered by thepowertraib warranty

[redvett]

Your truck has no positraction it has G80 locking differential. Yes its covered, look in your owners manual under powertrain warranty.

 

Is positrac covered by thepowertraib warranty

[cbrown4390]

What does a locking diff mean

[redvett]

The G80 is a Eaton product and you can read about it here.

http://www.eaton.com/EatonCom/Markets/Auto...tials/index.htm

 

What does a locking diff mean

[cbrown4390]

i can never get both my tires to spin is that normal

[C. Charles Hahn]

i can never get both my tires to spin is that normal

 

Torque Management. Get a tune.

[C. Charles Hahn]

The G80 is a Eaton product and you can read about it here.

http://www.eaton.com/EatonCom/Markets/Auto...tials/index.htm

 

What does a locking diff mean

 

 

Just to clarify, G80 is NOT the name of the Eaton product, G80 is the RPO code that GM uses to designate an Eaton locking differential in trucks, and a limited slip differential in cars.

[hodo78]

i can never get both my tires to spin is that normal

 

 

First question should be. Are you sure your truck came with the G80? The G80 does not come in Every GM 4x4 truck to my knowledge.

 

Or at least they didnt in the GMT-800 series. I had a '04 LS 4x4 model that DID NOT have the G80. It just had a open diff.

 

 

If you do in fact have one, you have to have one of your rear tires spinning at a certain speed ( Something like 25mph, im not sure) before the G80 locks and kicks in the opposite rear tire.

 

I am sure some of the pro's will be along shortly to correct my here if I am wrong, but this has always been my understanding of the several trucks I have owned with the G80 sans my '04 LS of course.

[Starrman]

so how does the G80, or Eaton Locking Dif, mechanically differ than a limited slip unit?

 

I'm very familiar with how the Ford trac-lok limited slips work and have rebuilt them very tight using extra clutches and they act like a posi unit but will allow a bit of slippage so it doesn't bind/pop going around corners, etc.

[georgecdisc]

so how does the G80, or Eaton Locking Dif, mechanically differ than a limited slip unit?

 

 

[Starrman]

so how does the G80, or Eaton Locking Dif, mechanically differ than a limited slip unit?

 

 

 

 

 

Great video that explains a lot.

 

So it still uses clutch packs behind each side gears like on most limited slip diffs, plus an additional ramped cam plate and engagement mechanism and pawl to activate it.

 

On a high power/torque or high shock application I'd be afraid of having those small parts of the engagement mechanism and pawl in there to break or come loose

[Badass69]

so how does the G80, or Eaton Locking Dif, mechanically differ than a limited slip unit?

 

 

 

 

 

Great video that explains a lot.

 

So it still uses clutch packs behind each side gears like on most limited slip diffs, plus an additional ramped cam plate and engagement mechanism and pawl to activate it.

 

On a high power/torque or high shock application I'd be afraid of having those small parts of the engagement mechanism and pawl in there to break or come loose

 

 

 

It does break a lot.... in 8.5" and 8.6" 10 bolts especially. You don't need huge tires, drive like an idiot or anything else stupid for it to fail. The governor/flyweight assembly works to actuate it in the event of tire slip. I can't watch the video but it should tell you that it works on differential rpm of the axles at low speeds only. At anything less than approximately 25 mph if either axles differs by around 150 rpm from the other the flyweight engages the locking assembly, forces the side gears into the clutch packs and becomes a locker. When locked it is just that, locked.... The clutches just dampen the locking action. Then if wheel speed goes above 25 mph or the axles turn at the same rate, it unlocks again.

 

It's trying to act as a locker than any Joe Blow can drive with. The problem stems from the fact the unit essentially shock loads itself everytime it actuates. Some guys have them last forever....... but they are usually the same guys that could drive around with an open rear end and be fine as well. If never needed or used, it never breaks. They don't always blow apart either.....a good chunk have the governor gears strip out and then it becomes permanently open.

 

I don't like the action of the unit myself....... give me a good clutch pack limited slip and it will handle all I want. A limited slip is easily rebuildable and lasts for a long time before requiring service. Gov locks........ well whatever. And for the true 4 wheeling crowd they will get a real locker as strain and load on a Gov Lock is guaranteed failure. The 9.5" and larger ones hang in there that much longer, simply because the parts are larger and thus stronger.

 

And to the OP, just look in your glove box at the sticker. If the code G80 is present you have a Gov Lock. If not then you have an open differential. No burnouts or diff cover removal required.

[brainpause]

Nice video. I'm surprised these diffs don't grenade the first time they're used. To think that two tires under mechanical stress are held together with a pawl.....

[redvett]

I have 3 service trucks 2000-01 & 03 the oldest has 255K and none have had the G80 go bad. Big tires, stupid driving will ruin any drive line. BTW these trucks are #1500 4x4, EXC, G80 and tow an enclosed trailer to the job site every working day.

[Badass69]

I have 3 service trucks 2000-01 & 03 the oldest has 255K and none have had the G80 go bad. Big tires, stupid driving will ruin any drive line. BTW these trucks are #1500 4x4, EXC, G80 and tow an enclosed trailer to the job site every working day.

 

 

Exactly......... there will be hundreds of stories like this pop up of course. If you never use it, it never breaks. Problem is you don't need abuse to make the thing fail. It just does that all on its own. It's a weak, poorly designed half @SS attempt at a locker that may or may not fail.