G80?

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George B

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If I remember correctly f both wheels are off the ground and one turns the opposite way when turning the other the gov-lock wont notice the difference and actuate. If one wheel stays stationary and the other can spin the difference is noticed and it locks. I can lock mine by hand with one wheel off the ground if I spin the wheel fast enough.
 

JonnyTahoe

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If I remember correctly f both wheels are off the ground and one turns the opposite way when turning the other the gov-lock wont notice the difference and actuate. If one wheel stays stationary and the other can spin the difference is noticed and it locks. I can lock mine by hand with one wheel off the ground if I spin the wheel fast enough.
I am going to see if I can get mine to lock by hand today.
 

JonnyTahoe

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I've never done that test myself but heres my thought process on it. Initially the locker will be open causing just one wheel to spin, as the rpm differentiates between the wheel (120rpm difference) that's spinning and the idle wheel. The locker will lock, which although a lot of people claim to never notice can be rather violent as its suddenly forcing both tires to move together almost like dumping a clutch. I notice it in my Tahoe occasionally especially in sand at low speeds.

If i remember correctly once the differential notices less load and a higher overall speed the locker will unlock. So if it's on jack stands it might be locking and unlocking in quick session.

Hopefully that makes sense. I dislike mine for aggressive driving because it seems to lock and unlock during my manual trans gear changes. With an auto if you never lift off the throttle it will likely stay locked due to the converter keeping the drivetrain loaded up.

Also G80s dont typically wear out, they just detonate spontaneously.
Locking and unlocking in quick succession that is exactly what it does and it sounds Harsh when it does it. Normal driving on the road its fine.
 
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Dantheman1540

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Locking and unlocking in quick succession that is exactly what it does and it sounds Harsh when it does it. Normal driving on the road its fine. I remember when we where at the drag strip these guys would have cars on floor jacks ''warming up'' the diff fluid that's what gave me the idea to run the rear wheels off the ground on a floor jack in gear to see what it does.

It is a good test because it shows that it's still able to lock and unlock effectively. Lots of drag racers full time locked differentials like a spool which would lock both side together all the time no matter what, making them sucky to drive on the street.
 

JonnyTahoe

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It is a good test because it shows that it's still able to lock and unlock effectively. Lots of drag racers full time locked differentials like a spool which would lock both side together all the time no matter what, making them sucky to drive on the street.
Did more testing. Backed up into the garage cement floor is real smooth from a dead stop it will hardly spin the tires it just hooks up and leaves two tire marks about a foot long ea. Test-2. I have a steep driveway, stop at the bottom facing the garage. Floor it leaves two marks about a foot long again totally Hooks up Both wheels.
 
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Dantheman1540

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Did more testing. Backed up into the garage cement floor is real smooth from a dead stop it will hardly spin the tires it just hooks up and leaves two tire marks about a foot long ea. Test-2. I have a steep driveway, stop at the bottom facing the garage. Floor it leaves two posi marks about a ft long again totally Hooks up Both wheels. Test-3.Last winter from a slow roll on packed snow Posi every time nearly identical length marks.

Sounds like its working good, I always approve of burnouts even if they are small :happy107:
 

Dantheman1540

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@jonnytahoe So this is a coincidence. I stopped by my buddies shop today to check on the rear axle hes welding stuff on for me and I saw his 2007 Avalanche on jack stands. Turns out he thought he blew up his G80 because it acted funny and when he puts it in gear on the stands it jerks around and makes bad sounds. I watched and it did exactly what we all determined above was normal. Yay for him no broken G80, downside is I think either the converter or something internal on the tranny is FUBAR.

Just another reason to love the forums even if you didn't think you'd need to know something it might come in handy.
 

JonnyTahoe

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@jonnytahoe So this is a coincidence. I stopped by my buddies shop today to check on the rear axle hes welding stuff on for me and I saw his 2007 Avalanche on jack stands. Turns out he thought he blew up his G80 because it acted funny and when he puts it in gear on the stands it jerks around and makes bad sounds. I watched and it did exactly what we all determined above was normal. Yay for him no broken G80, downside is I think either the converter or something internal on the tranny is FUBAR.

Just another reason to love the forums even if you didn't think you'd need to know something it might come in handy.
Sounds like what happened to my Tahoe almost two years ago. Trans started Jamming up at really slow speeds like coasting down the driveway in neutral. He may find small parts in the trans pan like I did.
 
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