Tahoe auto rear diff lock mystery

[khurramm]

The 2014 Chevy Tahoe is commonly equipped with a G80 automatic locking rear differential. .This differential is designed to automatically engage when a speed difference of approximately 100 RPM or more is detected between the rear wheels. This locking mechanism enhances traction in slippery conditions like snow or off-road situations.

Anyone with ideas on what is the easiest war to test this on my car??

@GauravI think you mentioned something similar to me during the master class.

During my research, I came across few references saying that this was/is offered only on some variants but another one mentioned all GM/Chevys trucks have this feature unless they have an electronic diff lock.

I am excited but clueless!

Now that I think about it, there is a diff lock symbol just below the 4wd controls in the car. I hope some light blinks on it when it becomes active (if only)!!

[Luke K P]

The Mystery Deepens!

 

[Frederic]

11 hours ago, khurramm said:

The 2014 Chevy Tahoe is commonly equipped with a G80 automatic locking rear differential. .This differential is designed to automatically engage when a speed difference of approximately 100 RPM or more is detected between the rear wheels. This locking mechanism enhances traction in slippery conditions like snow or off-road situations.

Anyone with ideas on what is the easiest war to test this on my car??

@GauravI think you mentioned something similar to me during the master class.

During my research, I came across few references saying that this was/is offered only on some variants but another one mentioned all GM/Chevys trucks have this feature unless they have an electronic diff lock.

I am excited but clueless!

Now that I think about it, there is a diff lock symbol just below the 4wd controls in the car. I hope some light blinks on it when it becomes active (if only)!!

The G80 rear differential is a limited slip differential, which is not the same as a locking differential. 
 

Limited slip differential means that the real wheels will only allow for a limited amount of spin. If you are not sure if it’s still working properly, you can just jack up the rear of the car and spin one of the rear wheels.

If the limited slip differential works then the opposite wheel will turn in the same direction. If you have a regular open differential it will turn in opposite direction.

i have the same G80 rear differential on my Isuzu Trooper. Its a nice thing to have but not a replacement for an actual rear locking differential.

The light on the dash might be for some models that have the full locking differential. LSD is fully mechanical so I don’t think there would be a light indication. 

[_Herman_]

That would indeed work if it is an LSD, but if it really is a locker that only engages at more than 100rpm difference, you will not make that rotation speed by hand.

It is supposedly a spring-loaded automatic locker.

Confusingly, both systems exist under the “G80” name.  So you are both right.  

[Gaurav]

13 hours ago, khurramm said:

Anyone with ideas on what is the easiest war to test this on my car??

When speed drops below 6 km, rear gets locked for equal power split on left & right tires. I recall seeing this on very old chevy YT video, where they were bragging about this in an off-road test.

You must have already felt this in action in your off-road drives. In some dunes while climbing when you leave the gas early and push the gas again when the car slows down and still able to cross the dune without getting stuck. This is only possible with LSD or Chevy proprietary tech of fully locking rear diff below 6 km.

[khurramm]

11 minutes ago, Gaurav said:

When speed drops below 6 km, rear gets locked for equal power split on left & right tires. I recall seeing this on very old chevy YT video, where they were bragging about this in an off-road test.

You must have already felt this in action in your off-road drives. In some dunes while climbing when you leave the gas early and push the gas again when the car slows down and still able to cross the dune without getting stuck. This is only possible with LSD or Chevy proprietary tech of fully locking rear diff below 6 km.

I have definitely noticed this happening where I had no hope of making it but the car crossed anyways..😁

[Gaurav]

Btw, it's no longer proprietary tech as I have seen this in the new defender in more than 5 Masterclasses.

[Frederic]

1 hour ago, Herman G said:

That would indeed work if it is an LSD, but if it really is a locker that only engages at more than 100rpm difference, you will not make that rotation speed by hand.

It is supposedly a spring-loaded automatic locker.

Confusingly, both systems exist under the “G80” name.  So you are both right.  

Oooh wow, i assumed both G80 differentials are the same. just looked it up and you are right. As the Isuzu had a GM tie-up at the time, i thought they'd be identical.

 

In my specific model its a pre-1998 LSD unit. The next year they came with a push button 4x4 engage with Track Lock (same as GM G80)

 

From Isuzu forum:

in the older 12 bolts (pre-1998) the LSD's are called Power Brute...used mainly in the mid 90's 2nd gen auto trans trucks.

in the 1998-2002 "modified 12 Bolt" in the trooper....the LSD is actually a Track-Lok.

[M.Seidam]

https://www.instagram.com/reel/DEh8yJACLEZ/?igsh=NTBjc2llb3JiajU0

[_Herman_]

On 6/27/2025 at 12:32 AM, khurramm said:

The 2014 Chevy Tahoe is commonly equipped with a G80 automatic locking rear differential. .This differential is designed to automatically engage when a speed difference of approximately 100 RPM or more is detected between the rear wheels. This locking mechanism enhances traction in slippery conditions like snow or off-road situations.

Anyone with ideas on what is the easiest war to test this on my car??

@GauravI think you mentioned something similar to me during the master class.

During my research, I came across few references saying that this was/is offered only on some variants but another one mentioned all GM/Chevys trucks have this feature unless they have an electronic diff lock.

I am excited but clueless!

Now that I think about it, there is a diff lock symbol just below the 4wd controls in the car. I hope some light blinks on it when it becomes active (if only)!!

Easiest way to test?  Where I’m originally from, we’d say park 1 rear wheel on the pavement and the other on the wet grass.  Give it some gas and you’ll quickly see if you actually manage to drive off.  (RWD only) 

 

Ofcourse, the trouble in Dubai is finding wet grass that isn’t someones lawn.

Edited June 30, 2025 by Herman G
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