2012 Tahoe Z71 - 6L80 Transmission

[ecordell]

I just purchased my Tahoe 3 weeks ago (3/10/18). Everything seemed fine with the vehicle and we made the purchase. Three weeks later (3/31/18) the Tahoe quits moving and makes a terrible noise as if you are shaking around a can of nuts and bolts. It now sits at my mechanics shop and needs a transmission rebuild.

The problem with these transmissions (2008 - 2016 6L80) have this issue. There is a drum inside the transmission that has a weld on it that ends up cracking, which in turn affects the pump (I don't know what I'm talking about, just reiterating in broken English what I was told) and eventually transmission failure. GM knows about this issue and has done nothing to this point. The issue typically comes in around 100k ish miles. There are no aftermarket upgrades or newer versions. You simply have to use the parts from GM to rebuild the trans and that's it (which might last another 100k).

Oh btw, this is a $2400 - $2500 repair

Pretty sure I just got ****** on this Tahoe purchase!

 

[General Stalin]

Never heard of this issue you speak of. As far as I know the 6L80 is a robust and reliable transmission so long as you aren't trying to push it beyond it's capabilities. I've got a 2007 Denali with the same 6L80 in it that it rolled out of the factory with; it's got nearly 200k miles on it and I've done literally nothing to it. I haven't even replaced the fluid or filter....

The only problem I've ever had transmission related was the bushing that attached the shifter linkage onto the shifter lever on the side of the tranny rotted out so I replaced with with a rubber grommet I bought at Ace hardware.

Sorry you bought a lemon though :\

 

[Doubeleive]

I just purchased my Tahoe 3 weeks ago (3/10/18). Everything seemed fine with the vehicle and we made the purchase. Three weeks later (3/31/18) the Tahoe quits moving and makes a terrible noise as if you are shaking around a can of nuts and bolts. It now sits at my mechanics shop and needs a transmission rebuild.

The problem with these transmissions (2008 - 2016 6L80) have this issue. There is a drum inside the transmission that has a weld on it that ends up cracking, which in turn affects the pump (I don't know what I'm talking about, just reiterating in broken English what I was told) and eventually transmission failure. GM knows about this issue and has done nothing to this point. The issue typically comes in around 100k ish miles. There are no aftermarket upgrades or newer versions. You simply have to use the parts from GM to rebuild the trans and that's it (which might last another 100k).

Oh btw, this is a $2400 - $2500 repair

Pretty sure I just got ****** on this Tahoe purchase!

that part is called a torque converter and yes that is the part that fails and takes the pump with it, yes it is a known issue. you can have a better more reliable converter put in when they do the repair so that it might possibly last longer next time around.

 

[ecordell]

The drum I'm talking about is 1 of the two drums inside the transmission that contain the clutches. I know what the torque converter is lol.

Never heard of this issue you speak of. As far as I know the 6L80 is a robust and reliable transmission so long as you aren't trying to push it beyond it's capabilities. I've got a 2007 Denali with the same 6L80 in it that it rolled out of the factory with; it's got nearly 200k miles on it and I've done literally nothing to it. I haven't even replaced the fluid or filter....

The only problem I've ever had transmission related was the bushing that attached the shifter linkage onto the shifter lever on the side of the tranny rotted out so I replaced with with a rubber grommet I bought at Ace hardware.

Sorry you bought a lemon though :\

The stealership decided that they would basically pay half (a little more) and gave me $1600 towards the rebuild of the transmission. Guess I should consider myself lucky on that. I'm starting to wonder if I should get a better trans cooler for the tahoe (the 6l80 is a high heat generator)....

 

[Doubeleive]

The drum I'm talking about is 1 of the two drums inside the transmission that contain the clutches. I know what the torque converter is lol.



The stealership decided that they would basically pay half (a little more) and gave me $1600 towards the rebuild of the transmission. Guess I should consider myself lucky on that. I'm starting to wonder if I should get a better trans cooler for the tahoe (the 6l80 is a high heat generator)....

I put a flex a lite on mine and a B&M trans pan, the flex a lite was very to install, just disconnected the stock one and drilled to new mounting holes for the flex a lite and bam it was done, I could go with a even bigger one easily

 

[Doubeleive]

The drum I'm talking about is 1 of the two drums inside the transmission that contain the clutches. I know what the torque converter is lol.



The stealership decided that they would basically pay half (a little more) and gave me $1600 towards the rebuild of the transmission. Guess I should consider myself lucky on that. I'm starting to wonder if I should get a better trans cooler for the tahoe (the 6l80 is a high heat generator)....

the local big wig transmission shop here told me the most common thing with these 6l80 is the torque converter going out and taking the pump with it, otherwise there pretty good.

 

[ecordell]

the local big wig transmission shop here told me the most common thing with these 6l80 is the torque converter going out and taking the pump with it, otherwise there pretty good.

I did ask him about that. He did say that is also a possibility and that the only way to tell for sure what happened was to rebuild it (with upgraded parts). The trans still hasn't been dropped because I was fighting with the dealership to fix it. He starts on it the first of next week.

I'm gonna stop in there and talk to him and see if he thinks adding a bigger trans cooler and upgrading the torque converter should be done. Mind you this is my wifes vehicle and it's just a "take the kids to school, go to work, light traveling" vehicle.

 

[Buzzcut]

Fwd clutch drum. Common issue on 4l60 e. Guess gm didn’t fix this.


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[raidernationmike]

my 2009 Yukon Denali was having hesitation issues in stop/go traffic and having a hard time downshifting back into first gear. Normal and high speed, no issues. But with LA stop/go I'd have situations where it would not go back into first and in a full stop i was starting my acceleration in 2nd gear. If i shut off the ignition and open the door and then start the engine back up, it would go back to normal and into 1st gear. it's over 150k now and i decided for a full rebuild ($3500 incl labor). Sucks!

 

[raidernationmike]

I just purchased my Tahoe 3 weeks ago (3/10/18). Everything seemed fine with the vehicle and we made the purchase. Three weeks later (3/31/18) the Tahoe quits moving and makes a terrible noise as if you are shaking around a can of nuts and bolts. It now sits at my mechanics shop and needs a transmission rebuild.

The problem with these transmissions (2008 - 2016 6L80) have this issue. There is a drum inside the transmission that has a weld on it that ends up cracking, which in turn affects the pump (I don't know what I'm talking about, just reiterating in broken English what I was told) and eventually transmission failure. GM knows about this issue and has done nothing to this point. The issue typically comes in around 100k ish miles. There are no aftermarket upgrades or newer versions. You simply have to use the parts from GM to rebuild the trans and that's it (which might last another 100k).

Oh btw, this is a $2400 - $2500 repair

Pretty sure I just got ****** on this Tahoe purchase!

Same issues: tech module issues, drum/weld point crack, How many miles on your Tahoe?