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posi units

RPO code G80 'Gov-loc' (lock) probably maybe.

The kind that goes BOOM when you have it floored when you're stuck real good. Although mine has survived 25 years. Somehow.
 
So if it's getting grabby going around corners it's probably a sign of going out? Thought I heard something too.
What's a good replacement? I had an Auburn posi in my firebird many moons ago, I liked it.
 
I bet the auburn posi unit would do you good with all the snow y'all get up there.

I had Detroits in the front and rear of my 72 blazer and they held up to a lot of abuse.
 
I run an Auburn cone style in my 74 C10, think they called it a 'pro diff' at the time. Quality piece.
 
The Auburn pro diff has a tight action and could see where it'd be more of a handful on the ice. Most clutch types do add some resistance in turns.

I would look into the Detroit True Trac for everyday stuff. My Camaro has one from the factory and you can't tell any resistance at all in turns, or spinning the tires by hand while hoisted..It's totally open. Have driven it 17 years now in all weather.. When power is applied it'll send it to both wheels. It still is an 'open' differential but has some weird spider gears that make it all work somehow.

Speaking of spider gears, if you clunk in turns you got some chipped probably. The Gov-loc is a plain open diff until the fly weights detect some amount of wheel spin then CLUNK the other side engages. Or if the right foot is heavy,.. BOOM.

The danger of chips of course is when/if they make it to where the ring and pinion hang out.
 
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I think there's a selectable electric locking diff to be had. It's pricey IIRC. Never messed with one tho.

Like Chris said, rebuilding the gov-lov is an option. They do work if you hold your mouth right. :nailbiting::)
 
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If you have the 10.5" full floater, then no, theres not alot of options out there. In 09 all there was was the gov bomb, open diff, the detroit locker that went inside of an open diff, I believe there was a cheaper insertable ratchet locker for an open diff, an arb air licker, and there was 1 clutch type limited slip for like $900. True trac makes one now, and I think I saw a reasoneably priced clutch type one, hut still not as many options as say a 10 bolt or even the 9.5" semi floater,
 
ak diesel driver said:
So will it damage any thing I wouldn't be replacing anyway if I let it go for awhile?
Click to expand...
Have You tried changing the lube ?
I`m not sure about Your locker but the one I just rebuilt for My son, in a 2000 dodge 1500, it required some differential friction modifier that keeps them from making noise and being so harsh.
 
MrMarty51 said:
Have You tried changing the lube ?
I`m not sure about Your locker but the one I just rebuilt for My son, in a 2000 dodge 1500, it required some differential friction modifier that keeps them from making noise and being so harsh.
Click to expand...
GM does not require the friction modifier like others since the clutches are not pre loaded. A G80 is only supposed to be active once wheel speed is between 10-25 mph, and there is a 50(don't remember the exact number, but it's quite a bit of difference required to engage the flyweight) rpm difference between the 2 tires. Alot of people let out of the throttle thinking they're broken before the wheel speed ever gets high enough to engage them. Then theres those who hammer them trying to lock it in, and exceed the speed it will work at.

Edit: found this tidbit straight from GM in a tsb regarding G80 operation specifically stating NOT to ever add friction modifier to one.
Important: Installing any friction modifier causes the clutch pack in the locking differential to slip and miss engagement. A fluid flush can often remove debris that is a contributor to clutch chatter. Adding friction modifier additive can cause a loss of locking differential functionality.
 
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ak diesel driver said:
Put a full tube of additive in and so far so good
Click to expand...
Get it out. Also of note, the 10.5" rear axle uses steel clutch plates full of holes, not a clutch plate with a fiber type clutch material. They are supposed to provide more holding during situations when the G80 is unlocked. GM even has a tsb stating the 10.5" may chatter or feel grabby during parking lot type situations, and that it is normal expected operation for one to do so.

Notice: Eaton locking differentials used in 10.5 rear axles are equipped with steel clutch plates. It is a design characteristic of these steel clutch plates to exhibit more clutch chatter than other models.
 
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