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Every 2nd Matters
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Discussion Starter #1
This weekend I was moving my cars around to work on the exhaust of Barricade. After the recent rain/snow that we got, my yard was a bit more soft than I anticipated and I got stuck. I tried to rock Barricade back and forth a little but could not get him to get traction. It then dawned on me... "hey only one wheel is spinning!" What gives? I thought the LSD was supposed to send torque to the "other" wheel in the event of no traction? I didn't floor it because I didn't want to dig myself in more than I already was. I have done many 2 wheel burnouts in the past with no issues. Am I expecting too much from the rear end?
 

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Every 2nd Matters
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Discussion Starter #3
Yeah. It is part of the 9c1 package. I have verified it on numerous occasions by doing 2 wheel burnouts on blacktop.
 

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Its a 25 RPM difference between the two wheels. So if it is a RPO/spid G80 then you might not have got on the gas enough to get it to lock up. With my 91 caprice i have the grass removed under one of the wheels just before the rearend locks up. On ice and snow it's hard to tell if you have that bit of wheel slip in going in a straight line. The g80 is made so you can turn corners without spinning the inside wheel on a dry gorund. If you are spinning in a corner the the clutch packs require service. Gm also recomends the limited slip additive when useing mineral gear oil, i would check with gm parts to see if the new oils need or dont need the additive.
 

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The b-bodies got a Auburn clutch posi not that stupid gov-loc the trucks got. The f-bodies got a gear driven torsen posi. Three different systems and I know for certain the b-body and trucks both used G80 code to indicate it probably the same code on the f-bodies too.

Papa D your posi is probably just getting a bit weak and even in perfect shape they can't cope with a huge traction difference very well.
I also believe it was a common OPTION on the 9C1 not standard.

My truck has the gov-loc which requires the wheel speed difference, it might be good in deep snow,mud, or sand but for a street vehicle it absolutely sucks and the sudden hammering engagement has earned it the nickname gov-bomb because if the other tire has good traction when the governor tried to engage it the shock can break things. If you have one tire on ice and the other on dry pavement it almost feels like getting hit by another car at lowish speeds..
 

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Discussion Starter #6
So I checked the build sticker and it says I have a Gu4, but I did a standing 2 wheel burnout when I first got this car. I have also done them in the dirt here in Arkansas. I gotta jack the car up this weekend and see wtf is going on.
 

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So I checked the build sticker and it says I have a Gu4, but I did a standing 2 wheel burnout when I first got this car. I have also done them in the dirt here in Arkansas. I gotta jack the car up this weekend and see wtf is going on.
RPO/spid G80 is gm posi id. GU4 is a 3.08 Rear Axle Ratio. Looks like this.
Caprice SPID codes
 

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It might have a G80 if i was replaced with one after the car was put on the road.
Or the trunk lid changed?
Make sure the vin matches the RPO/SPID vin # to be sure.
 

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To get out of snow, ice, or mud try this on a peg leg axle. Gently apply a few notches of your emergency/parking brake. You only want enough to keep the free wheel from spinning. Gently give the vehicle gas to get moving and once moving release the e/parking brake. This simulates a lsd/posi action for these conditions. Do not try this on dry pavement or heavy application of the accelerator pedal as you will do damage to the rear brakes and very possibly the rest of the drivetrain.
 

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Discussion Starter #10
So I confirmed it yesterday. I jacked the rear up and turned one tire while I watched as the other tire turned the opposite direction. I got an open diff. I just wanna know how I laid 2 rubber stripes when I first bought the car?:WTF:
 

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Divine Autosound
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To get out of snow, ice, or mud try this on a peg leg axle. Gently apply a few notches of your emergency/parking brake. You only want enough to keep the free wheel from spinning. Gently give the vehicle gas to get moving and once moving release the e/parking brake. This simulates a lsd/posi action for these conditions. Do not try this on dry pavement or heavy application of the accelerator pedal as you will do damage to the rear brakes and very possibly the rest of the drivetrain.
That's a really useful tip. I could have used that a couple years ago when I got my truck stuck in gravel and sand on a riverbed. If I had a locker or even a posi, I.wouldn't have got stuck, let alone buried it to the axle trying to get it out.
 

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So I confirmed it yesterday. I jacked the rear up and turned one tire while I watched as the other tire turned the opposite direction. I got an open diff. I just wanna know how I laid 2 rubber stripes when I first bought the car?:WTF:
Not sure this test you did confirms an open differential on a posi/lsd axle. For one the drive shaft input was not turning and if I understand the lsd/posi axles need that. On an open differential the axle wheels will turn opposite of each other even with the drive shaft turning.

If you truly have an open differentail then you could have just had the application of the accelerator just right or maybe the tires were new enough to have excellent grip to grab both wheels and spin the the correct directon. On my van I have confirmed through the build sheet that it has an open carrier axle and I have laid down two short stripes while backing up my driveway, while I wasn't even trying to.
 

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8th Gen Antagonist
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Mine always favored one side, then I did the bearings, and it would distribute the power pretty evenly, unless I get one wheel with significantly less traction, like mud or ice while the other gets traction.
 
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