G80?

[swathdiver]

These 1/2 ton Suburbans have a derivative of the 14-bolt?

The previous generation used the 14-bolt semi-floater when paired with the 6.2 motor and set up for RWD only.

OK so I have the 9.5" 12-bolt. I wonder why the Lock Right wants me to buy the part for the 14 bolt? Same innards as a 14-bolt?

Check over at DamandAAM.com and look at the charts and see if they share any parts. I thought they were wholly different but am no expert.

 

[Prospect62]

From a source:

"The GM 9.5" 12 bolt axle is a new version of the older GM 9.5" 14-bolt axle and is found under the rear of 2014 and newer GM mid-size trucks and SUVs with the 5.3L V8 engine. It features a large 9.5" diameter ring gear and accepts 33 spline semi-floating axle shafts. While similar, the 12 bolt and 14 bolt models of the GM 9.5" axle are different and gears, lockers, and internal components are not interchangeable.

The GM 9.76" 12 bolt axle is new and slightly stronger variation of the GM 9.5" 14-bolt axle and is found under the rear of 2014 and newer GM mid-size trucks and SUVs with the 6.2L V8 engine and/or a tow package. It features a large 9.76" diameter ring gear and accepts 33 spline semi-floating axle shafts."


Welp, my truck doesn't have the "Max Tow" package, but it does have a hitch...I really don't know what I have. There must be a way to tell for sure. I wish I had my build sheet here but it's on my work computer. Either way, this answers the question about the 14-bolt Lock Right stuff working - I guess the people at Lock Right have it wrong?

 

[Prospect62]

Apparently one could get a Detroit TrueTrac for the 9.5" 12-bolt...

https://eastcoastgearsupply.com/i-23993370-gm-9-5b-semi-float-detroit-truetrac.html

Pretty sure the TrueTrac is a good unit...but it's spendy and requires a more involved install. I was hoping for a drop in lunchbox locker. Perhaps someone will make one someday, in the mean time I'm plenty confident in the G80 and feeling much better knowing my rear end is pretty stout whether it's the 9.5" or the 9.76".

 

[Dantheman1540]

Apparently one could get a Detroit TrueTrac for the 9.5" 12-bolt...

https://eastcoastgearsupply.com/i-23993370-gm-9-5b-semi-float-detroit-truetrac.html

Pretty sure the TrueTrac is a good unit...but it's spendy and requires a more involved install. I was hoping for a drop in lunchbox locker. Perhaps someone will make one someday, in the mean time I'm plenty confident in the G80 and feeling much better knowing my rear end is pretty stout whether it's the 9.5" or the 9.76".

Unless you are getting really wild I'd keep the G80 since it's in a 9.5 and not a 8.6 10b. The one in my Tahoe does really well when towing a trailer in wet grass or loose sand. I haven't gotten stuck yet and it's 2wd. What it sucks at is sliding around corners.


True tracs are awesome though I am about to order one for a 14b I'm building.

 

[Captain Insaino]

I killed the one in my S10 at ~38K miles from asshattery coupled with a supercharger. Swapped in a stock Zexel from an '02 Camaro SS and never looked back.

Sorry, off topic. Did you have any issues swapping a torque arm suspension rear end into your S10? I have a lot of money into my 12 bolt and would like to swap it and my motor into a pre smog era car. It's getting harder and harder to work around the cert in Cal unicornia. "asshatery" Lol.

 

[iamdub]

Sorry, off topic. Did you have any issues swapping a torque arm suspension rear end into your S10? I have a lot of money into my 12 bolt and would like to swap it and my motor into a pre smog era car. It's getting harder and harder to work around the cert in Cal unicornia. "asshatery" Lol.

Oh, I just swapped the LSD itself. Swapped the ring gear from my S10's blown Gov-Bomb onto it and dropped it into the S10 10-bolt rear end.

 

[JonnyTahoe]

My RPO list says I have a G80. When I had the truck up in the air the other day, I spun the rear wheels and when one went forward, the other went backward. Any shadetree mechanic worth his salt will tell you that this would tend to indicate an open differential.

If I truly had the limited slip, both wheels should turn in the same direction. That's how it's always worked before, anyways.

Anybody know what's going on here? Does the good 'ol G80 work differently in this truck as opposed to the 5 or so other Chevy trucks I've had before?

Mine goes both directions as well.

 

[JonnyTahoe]

I have personally completely murdered 2 G80s in 10bolts and nearly killed a third. I agree that they are fine if you drive them gently, avoid wheel slip or any other scenario that would cause them to have a sudden shock load. I don't believe frequent oil changes will help them survive a sudden failure situation but it does certainly help the bearings.

Figured I would run this by you Dan. When I jack my 2000 Yukon G80 rear up off the ground and with the engine idling and trans in drive let off the brake and let the wheels spin freely at idle the drivers side wheel seems to lock-up as the wheels are rotating. Took it to a driveline shop and they said it was the diff Locking and un-Locking and said it was normal. Do you agree with that?

 

[Dantheman1540]

Figured I would run this by you Dan. When I jack my 2000 Yukon G80 rear up off the ground and with the engine idling and trans in drive let off the brake and let the wheels spin freely at idle the drivers side wheel seems to ''Jam up'' as the wheels are rotating. Took it to a driveline shop and they said it was the diff engaging and dis-engaging and said it was normal. Do you agree with that?

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.

 

[iamdub]

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.

Cosigned.

I set my rear on jack stands to let the wheels spin while I "machined" the lips on my de-clads. Idling in gear, the passenger side would spin as if it were an open diff. Once it reached that ~120 RPM difference, the driver side would suddenly and seemingly harshly engage. This sudden engagement loaded it down enough to slow it below that 120 RPM threshold, so the diff would unlock, letting just the passenger side spin again. The passenger side would accelerate until it reached ~120 RPM and the cycle continued.

I ended up disconnecting the speed sensor and using a cinder block to lightly press the throttle pedal to hold it at a speed just above the locking RPM so it'd remain at a steady RPM. I disconnected the speed sensor because the traction control nannies didn't like the rear wheels spinning and the front wheels not spinning and kept closing the throttle.

 

[George B]

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]

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]

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.

 

[Dantheman1540]

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]

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.

 

[Dantheman1540]

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

 

[Captain Insaino]

Oh, I just swapped the LSD itself. Swapped the ring gear from my S10's blown Gov-Bomb onto it and dropped it into the S10 10-bolt rear end.

Thanks, Chris.

 

[Dantheman1540]

@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]

@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.