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My 8-speed Auto Transmission is a Stumbling Drunk

InVision

By InVision
in Engines & Drivetrain

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JimCost2014 Senior Enthusiast

JimCost2014

Posted
Posted

I may be jinxing myself, but so far my 18 8 speed has been tremendously better than my 16 was. But, one thing is for sure, if it were advertised as, 8-speed Auto Transmission is a Stumbling Drunk, I am buying that truck just because.....

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InVision Enthusiast

InVision

Posted
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Posted

I noticed your 2018 is a 6.2L.  Was your 2016?  I drove a couple of 2018s and a 2019 with 6.2Ls and they did not drink from the same Kool-aide.  :-)  I was considering trading in for a 2019 Denali until I seen one. Did not care for it at all.  But it did not stumble.

 

Dropping off our Stumbling Drunk tomorrow...

 

M

InVision Enthusiast

InVision

Posted
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Day one at the GMC Service Shop.  Got a call at the end of the day.  Service manger said, "Yes sir you have an issue".  Said he is going to perform 3 or 4 updates and/or TSBs and re-test it tomorrow.  I will take the win that they at least said I have an issue.  It is getting colder here in NW Florida and the truck really stumbles around when it is first driven.  Stay Tuned :-) !

 

M

GPHusker Enthusiast

GPHusker

Posted
Posted

I posted in another thread but I just got my 18 Silverado 6.2 with 8 speed on 1/10. I am already having TCC shudder. I have an appointment for tomorrow to drop the truck off. 427 miles.....

SS502 Senior Enthusiast

SS502

Posted
Posted
On 1/19/2019 at 10:37 PM, JimCost2014 said:

I may be jinxing myself, but so far my 18 8 speed has been tremendously better than my 16 was. But, one thing is for sure, if it were advertised as, 8-speed Auto Transmission is a Stumbling Drunk, I am buying that truck just because.....

X2...no issues with mine YET ? but I have little doubt there is a problem. While getting my headlight changed, my service manager was sitting there talking to me about the new procedures for fixing this...yep it was the 3 flush/fill with newly developed fluid...they have the fluid but are waiting on parts to upgrade their equipment. Just having him discuss this tells me they are having problems but not on every single truck. His recommendation to me was not to wait if I start having problems. It may help that he’s a friend.

JimCost2014 Senior Enthusiast

JimCost2014

Posted
Posted
3 hours ago, SS502 said:

X2...no issues with mine YET ? but I have little doubt there is a problem. While getting my headlight changed, my service manager was sitting there talking to me about the new procedures for fixing this...yep it was the 3 flush/fill with newly developed fluid...they have the fluid but are waiting on parts to upgrade their equipment. Just having him discuss this tells me they are having problems but not on every single truck. His recommendation to me was not to wait if I start having problems. It may help that he’s a friend.

So, what are some of the signs that your transmission has been drinking and is now drunk?

InVision Enthusiast

InVision

Posted
  • Author
Posted
40 minutes ago, JimCost2014 said:

So, what are some of the signs that your transmission has been drinking and is now drunk?

Erratic shifting, stumbling and sort.

 

M

SS502 Senior Enthusiast

SS502

Posted
Posted
47 minutes ago, JimCost2014 said:

So, what are some of the signs that your transmission has been drinking and is now drunk?

When the transmission didn’t want to drink alone and exhaust smells like Jägermeister ? 

InVision Enthusiast

InVision

Posted
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Posted

Just pickup up Truck.

 

They flushed the transmission, convertor and lines, changed the fluid multiple times, replaced & reset the shift adapter.  Verified concern: FOUNDTCC Shudder.  Not sure what that means all considered.

 

THE TRUCK RAN GREAT & SMOOTH WITH NO STUMBLING OR ERRATIC SHIFTING.

 

If this is a sign of the future, I am in LOVE with my truck once more!!

 

M

JimCost2014 Senior Enthusiast

JimCost2014

Posted
Posted
4 hours ago, InVision said:

Erratic shifting, stumbling and sort.

 

M

Those I have heard about/experienced in my 16. Problem is, all of those will be considered normal characteristics of the transmission. There has to be something new that they are looking for to spend the money on the fix, otherwise there are going to be thousands of upset owners that were turned away before.

JimCost2014 Senior Enthusiast

JimCost2014

Posted
Posted
4 hours ago, SS502 said:

When the transmission didn’t want to drink alone and exhaust smells like Jägermeister ? 

It always has it's Buddy, Weiser and his pal Jim Beam...….

JimCost2014 Senior Enthusiast

JimCost2014

Posted
Posted
4 hours ago, InVision said:

Just pickup up Truck.

 

They flushed the transmission, convertor and lines, changed the fluid multiple times, replaced & reset the shift adapter.  Verified concern: FOUNDTCC Shudder.  Not sure what that means all considered.

 

THE TRUCK RAN GREAT & SMOOTH WITH NO STUMBLING OR ERRATIC SHIFTING.

 

If this is a sign of the future, I am in LOVE with my truck once more!!

 

M

Good to hear, just read this after I replied to your post.

JCKustoms Enthusiast

JCKustoms

Posted
Posted

All 3 (‘14+) of my 8 speeds have had issues. 2 with the 5.3 and 1 with the 6.2. All three were purchased new.

My ‘16 Silverado was the worst. Had it in 4 different times to the dealer for module updates. Of course the dealer couldn’t replicate anything I experienced. Didn’t really notice any difference after each update. Still had all of the symptoms everyone else is experiencing. Never had a fluid flush or change. Had 24k miles.

My ‘16 Sierra was not much better. Had 17k miles. Never to dealership.

My ‘18 Sierra definitely has the least issues, although different than the others. Waiting to take to the dealership. Has 6500 miles.


Sent from my iPhone using Tapatalk

SS502 Senior Enthusiast

SS502

Posted
Posted

Just read this said about the competitor's (spelled with four letters) 10 speed transmission "The 10-speed auto is generally a good transmission, but it gets confused easily in stop-and-go traffic, resulting in clunky downshifts." Now this is a fairly new transmission and already having some issues. I guess "generally good" is the new norm? I have a feeling the 2019 crowd with the 10 speed (co-developed with that other company) is going to be just as sorry as some of us 8 speed owners. 

 

Oh and I have not had any problems YET but it's defiantly a known issue with some owners... 

GPHusker Enthusiast

GPHusker

Posted
Posted

I have my 18 at the dealership this week for TCC Shudder issue. Talked to the service manager about the issue and he said they have been dealing with it for awhile. They called me later to confirm they agree I have the issue and after talking to GM they are apparently shipping them some of the new fluid. Supposedly the brand new fix stuff. We will see when I pick it up later today if it indeed works or what they actually put in it.

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