2019 Escalade ESV 10L80 (MF6) hesitating/shuddering

[jyi786]

Transmission exhibiting harsh shifting in all gears (1 through 10) and exhibiting what I think is TCC shudder. Getting a vibration/shimmy especially when feathering the throttle when the torque converter goes into lockup, which feels like driving over rumble strips. Tach RPM does bounce up and down which looks like TCC shudder. Vibrates the entire truck like mad until I either mash the throttle forcing an upshift, or take my foot off the throttle.

Shifting gears 1-3 feels ok after warm, but then when it tries to go to 4 or anything after, it searches hard, upshifts, and downshifts, bangs up/down into those gears, and also shudders. Symptoms highly evident when cold, gets much better when warm.

New and proper ACDelco ULV fluid as called for in the owner's manual installed and checked at 212F as instructed by ACDelco TDS.

@NickTransmissions do you have any thoughts? I have it scheduled for the stealership to look at it on Monday, but any insight based on your experience would be great.

 

[NickTransmissions]

Transmission exhibiting harsh shifting in all gears (1 through 10) and exhibiting what I think is TCC shudder. Getting a vibration/shimmy especially when feathering the throttle when the torque converter goes into lockup, which feels like driving over rumble strips. Tach RPM does bounce up and down which looks like TCC shudder. Vibrates the entire truck like mad until I either mash the throttle forcing an upshift, or take my foot off the throttle.

Shifting gears 1-3 feels ok after warm, but then when it tries to go to 4 or anything after, it searches hard, upshifts, and downshifts, bangs up/down into those gears, and also shudders. Symptoms highly evident when cold, gets much better when warm.

New and proper ACDelco ULV fluid as called for in the owner's manual installed and checked at 212F as instructed by ACDelco TDS.

@NickTransmissions do you have any thoughts? I have it scheduled for the stealership to look at it on Monday, but any insight based on your experience would be great.

Hi, unfortunately I have literally no experience with the 10-speeds as of yet, haven't seen one and only know the basics about them. That said, any shuddering is typically converter clutch slippage so will likely need a new one, at minimum...If caught early enough, there usually isn't damage to the front pump but if it's been going on for a while, pump may have been scored to the extent it begins to compromise volumetric fluid flow and corresponding adverse effects on shifting, drivability ,etc...The harsh upshifts/downshifts typically indicate worn applied elements or sealing surfaces as it's taking much more pump vol and line pressure, generated via RPMs to get the clutch to apply and when it does, its late relative to a healthy hydraulic circuit so the trans may have to come out...

Let us know what the dealership says once they've had a chance to diagnose it.

 

[Seamus]

The 10 speeds are pretty darn good in comparison to 6 and 8 speeds. I have had 3 and presently have 2 in the household. Love this trans and owned the others previously. BUT I have read of 2 converter issues and recently had a friend with a 2020 10 speed that the TC fail ( and was noisy) which then caused an issue with valve body. Warranty replaced both and did a flush and he is doing fine for now. So they also have TC issues at the least.

 

[jyi786]

The 10 speeds are pretty darn good in comparison to 6 and 8 speeds. I have had 3 and presently have 2 in the household. Love this trans and owned the others previously. BUT I have read of 2 converter issues and recently had a friend with a 2020 10 speed that the TC fail ( and was noisy) which then caused an issue with valve body. Warranty replaced both and did a flush and he is doing fine for now. So they also have TC issues at the least.

How often did/do you change the transmission fluid on the 10 speeds? Did you follow the severe schedule?

 

[Seamus]

The others were traded out early about 30K, so never did them. My truck now has 31K on it, and my tech said he would do it every 30K. Florida hot, and towing. My wifes 2018 was bought used and it was a soccor mom truck lightly used with 70K. I did it the week we bought it. Magnets were very dirty, fliter dark, fluid ok but I would never go 70K by choice. My friend who had the Tc issue and valve body bought used and was just under 50K. His truck was used as a truck and towed prior to his purchase. Adds to why I am going to change out the fluid and filter soon, and keep an interval 30-35K on diff and trans which I do at the same time. I have the fluid, pump, and filter sitting in the garage.

 

[Seamus]

As these 10 speeds get more miles, I am watching to see if the TC is an issue as it is on the 8 speed. The 8 speed started immediately once in production and continues to this day. Just a few 10 speed TC?/ So nothing near as bad as the 8 speed. Literally the aftermarket has the answer for the 8 speed and many do it upon a new purchase as preventive maintenance. 10 speed has been out a long time now. 6 years??

 

[jyi786]

Posting an update from my other thread. So it's been at the dealership since Monday morning.

...and as expected, the stupid dealership said they could not replicate it, so they assigned it to the "shop foreman", who also said he couldn't replicate it, and reached out to GM TAC for support.

I asked if they even listened to anything I said, because if you simply connected a bi-directional scanner to it and watched the graphs as you drove, you would SEE it.

I told them that you can 1000000000% replicate it, especially when the powertrain is cold. I offered to show up and take them on a test drive, which they accepted. I showed up, took the shop foreman on a test drive, and was able to replicate the issue in under 30 seconds. Additionally, I replicated it a whole bunch of times, so there was no question. So only THEN did the shop foreman say he would connect the scanner to it, drive it, gather the info, and then forward on to GM TAC.

So I'm obviously still playing the waiting game.

 

[jyi786]

Finally an update.

The dealership had my truck since Monday morning. On Tuesday evening, I called them asking for a status update. They said they'd have an update for me later that evening. I never got that update. So I waited until Thursday morning, and called. What do you expect: I got the same old line. They assigned it to a tech, who "could not replicate the issue". So they assigned it to the shop foreman, who also "could not replicate the issue".

Incredulously, I said to them that it is 10000000% easily replicated, each and every time, and offered to come to the dealership again to show them. They agreed, and the shop foreman came along for the ride. Within 30 seconds of me getting into the driver's seat, I reliably replicated the issue, and made sure the tech actually felt the shudder at least 3 times. I asked him if he wanted to bring the scanner so that we can do it again, and he said no need, he had all that he needed to proceed.

Fast forward to this evening, I called them for a status update, and the service advisor reported to me that the shop foreman tech finally indeed did find "codes on the TCM" and on the output graphs which indicate clear TCC slippage. The reasoning they gave for "not believing" what I was telling them is that they have never seen a 10 speed transmission fail, and so were completely caught by surprise that it was indeed the case.

They said based on the diagnosis that it was one of three things:

1. Solenoid/s
2. Valve body
3. Torque converter

They said since it was narrowed down to those 3, they would start doing a more in-depth diagnosis in that order (which is also in order of ascending cost) to determine which of the 3 are the problem, and then provide me with an estimate on repairs early next week.

In hindsight, if they would have just done what I asked them to do, they could have saved me a wasted week, because I literally told them what to do, and expected that it was TCC shudder. Whatever. That is behind me now, and I need to focus on getting this fixed.

@NickTransmissions, what are your thoughts on which of the three it might be? I'm really hoping it's either the solenoid or the valve body, because I know from experience that these two are much less expensive than the actual torque converter.

 

[jyi786]

Final update:

Got my truck back yesterday. Engine oil leak was fixed, radiator flushed, trans cooler lines flushed and checked for leaks, and new transmission installed.

As for the issue: shuddering is completely eliminated. New transmission shifts slightly hard very rarely, but that's most likely because it needs to learn/adapt to my driving style. No more shuddering to speak of. All gear shifts up or down are as smooth as can be. Dealership confirmed in writing that if the transmission would fail due to the radiator, it would be covered under warranty, but not the radiator (which is to be expected).

All is well. I guess I'll never know what failed in the old transmission, but all I can do is look forward to the future, and ensure that this doesn't happen again. Transmission will be serviced dutifully at every 30k miles.