'86 Chevy LSD

Zorba

"The Veiled Male"
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This is a dumb question, but as I just "don't know", I figured I'd ask it here. Had an '86 Chevy C10 2WD with a 3.08 LSD/Posi/Whatever. Just after we bought the truck, I drove it over to my parent's house that had a fairly steep paved driveway, with Iceplant on the side. People were forever and always getting stuck in the Iceplant - VERY slick. So to test my fancy new truck, I purposely drove one side into the Iceplant on my way up the hill. As expected, that wheel started to spin, so I backed out of the throttle. As I did so, there was a VERY "hollow sounding" clunk and the rear of the truck kind of twitched. I then gave it throttle and the the other wheel that was still on the pavement pulled it on up the hill.

Was this the "normal" clutch pack type LSD, or something else? What was going on?

The only other experience I had with it was a couple of years later was learning that "positraction" can mean you have to dig out two wheels instead of just one! Both rear wheels dug in on a sandy-soiled hill until the pumpkin stopped further downward travel of the axle! :ROFLMAO: No clunking that time - they just both quietly dug in! Shovels are good things... ;)
 
That's a GM Gov -loc diff. kinda a auto locker vs a limited slip. when they work they are great but they were known for extreme reliability.
 
Were know, or WEREN'T known?

LOL how about weren't known for reliability !
But here again what type of locking diff did Ford or Dodge offer at the same time ? That's what I thought !
Don't you hate when you don't proofread your post worth a crap ! Thanks Zorba!
 
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The G80 gov-loc works fine when the tire diameter is kept stock, or near stock. With anything 33" or larger and any type of abuse, it doesn't hang around long.

With factory tires they can handle quite a beating.

It is an often hated diff called a gov-bomb. I would not run one unless it was already in the truck and the tires were stock size.


They use centrifugal weights to slide a collar into the case and lock the spider gears to the case when wheel speed differentiates quickly, like mud or sand or ice. It can be a harsh engagement.

When equipped with 35's and burnouts or wheeling the case liked to shatter into lots pieces when the "locking" action took place. I've been in an 87 k10 when this happened, doesn't sound pretty.
 
They use centrifugal weights to slide a collar into the case and lock the spider gears to the case when wheel speed differentiates quickly, like mud or sand or ice. It can be a harsh engagement.
Now that you describe it, it *does* sound like it could be very harsh! The truck was completely stock.
 
I would hope so. Especially in FL where they're trying to keep cool, and skirt probably helps them with that but I hope it's not a short skirt.
Usually mid-calf length - or ankle for dance costumes. I had a mini once - you have to plan EVERY move you make in one. How you walk, how you sit, how you go up stairs, how you bend over (you don't), blah, blah, blah. It was interesting, but far too much hassle.
 
IIRC a difference of 150 RPM in the two wheels that will cause the "grenade loc" as their known to do its thing. Our genital motors Z71 has it and can be a tad unnerving at times when it locks up.
 
IIRC a difference of 150 RPM in the two wheels that will cause the "grenade loc" as their known to do its thing. Our genital motors Z71 has it and can be a tad unnerving at times when it locks up.
I never had any problems with the thing, but it was stock with stock wheels and a 305 - unfortunately, a 305 V8, not a 305 V6!
 
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Positraction is the name GM use for the Eaton Limited Slip (Eaton still calls their aftermarket limited slips Posi) they used in many applications. What you are describing as others have noted is the Gov-Lock (aka G80) governor locking diff. It uses a fly weight to "sense" the difference in wheel speed from one side to the other and add pressure to the clutches as needed. Problem they have is that they do not like extreme differences in wheel speed which has the habit of sending the fly weight out the cover. That is where the Gov Pop or Gov Bomb name come from.
 
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What was your axle ratio? Our '63 got about 10 with 5.14. Uphill or down, loaded or empty. But the V6s were never put into Chevys! ;)

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