Looking for a locker for my 02 HD. It didn't come with one (I checked the build sticker in the glovebox), and I need one for desert trips, snow, etc. Anybody put an aftermarket unit in yet? Thanks!

To the best of my knowldege, there are still no aftermarket lockers available. I've heard that some are in the works, but ETA unknown. Your choices are the G80 Eaton Gov-Lok limited slip or you can get a factory Dodge limited slip which is a helical gear like a TruTrac.

it should be pretty easy to put in a factory Gov-Loc...the Gov-Loc, while maybe not the most desirable locker, is actually a true locker, whereas the Dodge trac-rite is more of a limited slip.

Ben

please do not quote me on this but, I believe my truck has a Locker with 3:73 ratio. I bought the truck last monday, and looking at the axle it has written on the rear from the salvage yard ( Locker 3:73) and some other Garb. When you make a sharp turn it does chirp the inside tire. So I dont know if this confirms this theory. Anyway I bought this truck because I saw on this site that the 01-02 duramxs where the most fuel effiecient and so far I am very happy. Went to Macon Ga, and went 400 miles averaging 78 mph if possible and put 20 gallons in , you do the math. I f a standard rear xle will do better on economy great. I didnt buy the truck to do any 4 x 4 or pulling anything heavy. I bought it strictly for economy, coming from a Hemi Dodge getting around 15.5 mpg at 78 mph. And I am in hopes to mix in some veggy oil here and there to clean our environment up .:ro)

If it has "G80" on the option sheet in glovebox then it has the locker. If it does have it and it chirps on sharp turns, you may want to pull rear diff cover and see if Governor gear is missing a tooth or two. It is on the diff case spanning the opening in the case

The G80 is a limited slip and not a locker. It is a free-wheeling limited slip which is supposed to not be noticeable to the driver which is good for economy and tire wear. When one tire spins, the gear mechanism provides connection and side-load to the clutch plates which makes for the limited slip action.

The G80 is a "locker"...not a limited slip. It uses flyweights to engage a true locker, not clutchpacks. You dont need to run friction modifier or anything in it like you do with a limited slip....

http://automotive.eaton.com/product/traction_stability/lockingdiff.html

Ben

We seem to revisit this isse quite a bit. The G80 RPO code is used on both GM TRUE-TRAC limited slip and the eaton locker. In my experiance G80 eaton lockers are always behind the Duramax and 8100 with the Allison. We use the TRUE-Trac behind the 6.0 gas with the 4L80 trans. The TRUE_TRAC is easy to spot from the front load pinion,

We seem to revisit this isse quite a bit. The G80 RPO code is used on both GM TRUE-TRAC limited slip and the eaton locker. In my experiance G80 eaton lockers are always behind the Duramax and 8100 with the Allison. We use the TRUE-Trac behind the 6.0 gas with the 4L80 trans. The TRUE_TRAC is easy to spot from the front load pinion,

So I think your both correct, G80 can be a limited slip or a locker. Depend what lives under the hood.

I haven't broken a gov-lok in a late model truck, but I've blown up 4 of them in 12 bolts. And they are a gear assisted limited slip with clutches. They say it is "locked" but what it means is that maximum pressure is put on the clutch packs. This is why a Gov-Lok wears out and a Detroit locker does not. It is also why you must use limited slip additive in the differential and why a Tru-Trak and Detroit do not require them as they are true mechanical limited slip or locker respectively.
Taken straight from Eaton:


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.

Okay, so I have an 8.1....where is the best place to buy an Eaton unit for my truck? I've done rear gears before, I might not even have to mess with the pinion if it's the same as the 10.5" FF gearset.

Talk to tate and randys ring and pinion. I have the full yukon gear and the full rebuild kit. I also purchased the unlimited warrenty. The gears are stock (3.73) If you are going to install it yourself let me know.