Transmission valve body-no parts to be found

[jensenswanson]

My 2025 Yukon Denali with the 6.2 has been in the shop 5 weeks now awaiting a valve body. It only has 934 miles on it and I couldn't be more disappointed with the way GM has handled this so far. I have now been escalated to the "Parts Delay Department" where they will undoubtedly continue to feed me lines about how much they understand how frustrating this must be and how they are doing everything they can to rectify the situation as soon as possible.

I asked both the dealer and the GM rep if they have heard of the Nextgen kit and if they could use those parts as they appear to be better made and, perhaps even more importantly, are readily available. The answer I got from both was NO.

I also have big car payments to make for a BRAND NEW VEHICLE that has been at the shop way longer than we have had it on the road. Beyond mad and feeling incredibly frustrated.

So much for the theory that the '25 got better parts....

 

[jfoj]

@Staceyr72

Any update or progress with your situation? What was the problem with your vehicle originally? Harsh shifting? P0747?

 

[jfoj]

@Davefan

What were the symptoms of your vehicle that caused you to take it in?

Harsh shifting? P0747? Other?

 

[jfoj]

@jensenswanson

What were the symptoms of your vehicle when you took it in? Harsh shifting, P0747, other?

While GM says no to something lke the NextGen kit, I plan on probably proactively instaling it in my truck. If my truck was tied up for 5 weeks, I would pick it up and probably do the NextGen kit anyway. Does not really matter much as these trucks will likely get the software Recall like the Diesels and the 90,000 Cadillac sedans and Camero's. Just a matter of time. Then if the TCM software recall is released on these gas trucks, GM will likely then extend the valve body Warranty for 15 years - 150,000 miles like the Diesel trucks and the 90,000 Cady's and Cameros.

Anyone who is having valve body probems NEEDS to fill out a NHTSA complaint form, this can be done online. Understand the more complaints, the more likely and sooner the TCM software recall and valve body warranty extension will show up for the gas powered light trucks.

NHTSA Online Complaint Form

 

[jensenswanson]

@jensenswanson

What were the symptoms of your vehicle when you took it in? Harsh shifting, P0747, other?

While GM says no to something lke the NextGen kit, I plan on probably proactively instaling it in my truck. If my truck was tied up for 5 weeks, I would pick it up and probably do the NextGen kit anyway. Does not really matter much as these trucks will likely get the software Recall like the Diesels and the 90,000 Cadillac sedans and Camero's. Just a matter of time. Then if the TCM software recall is released on these gas trucks, GM will likely then extend the valve body Warranty for 15 years - 150,000 miles like the Diesel trucks and the 90,000 Cady's and Cameros.

Anyone who is having valve body probems NEEDS to fill out a NHTSA complaint form, this can be done online. Understand the more complaints, the more likely and sooner the TCM software recall and valve body warranty extension will show up for the gas powered light trucks.

NHTSA Online Complaint Form

It was rough shifting on the way home from the dealer, particularly while just cruising and feathering the throttle at or around 25-35mph. Also, pulling away from stop signs or lights. The easier we were on the throttle, the worse the shutter was.

We've been told that installing 3rd party parts will void the warranty. I'd like them to fix it, just sooner rather than later is the gamble were playing with here.

 

[jfoj]

@jensenswanson

Thanks for the response.

A few questions, no SES/CEL/MIL light came on?

Have you ever driven a vehicle with the DFM? Wondering if part of what you were felling was DFM kicking in and out?

Did the dealer pull the vehicle apart? If not, I would pick it up, and drive it with the Auto Stop/Start turned off and then operate the transmission ONLY in L9 and see what happens. At least you might have transportation for the time being.

As for voiding the warranty on the valve body, funny thing it is you were to have someone other than GM install the valve body kit, it would very difficult for a GM tech to even notice a difference in the valve body. GM techs would rarely disassemble the valve body, they would perform a direct exchange. Seems that the valve body problems are VERY prevalent and it is part of the design. Not sure what the newer valve bodies will have different that may help these problems. The metal seperator plate with the paper gasket appears to be a major internal leak point for the valve body, probably due to the difference in expansion and contraction between the aluminum valve body and the steel seperator plate. I am pretty sure the NextGen kit eleminates the paper gasket and has a thicker seperator plate. I know on one of the RAM truck kits they have a much thicker aluminum seperator or spacer they offer for that application.

Valve body problems are nothing new since most transmissions have switched to aluminum over cast iron for the valve body. Valve body wear due to valve gouging has been a big issue alone with internal leaks around the seperator plates.

Good luck and let us know what happens, seems MANY people have been parked for 4-5+ weeks at this point, hopefully parts will be moving out soon.

 

[jfoj]

@Blanch44

How long ago were you waiting on a valve body for 2 months? Recently?

What were the symptoms that caused you to take your vehicle to the dealer? Lights? Harsh shifting? Codes?

 

[jensenswanson]

@jensenswanson

Thanks for the response.

A few questions, no SES/CEL/MIL light came on?

Have you ever driven a vehicle with the DFM? Wondering if part of what you were felling was DFM kicking in and out?

Did the dealer pull the vehicle apart? If not, I would pick it up, and drive it with the Auto Stop/Start turned off and then operate the transmission ONLY in L9 and see what happens. At least you might have transportation for the time being.

As for voiding the warranty on the valve body, funny thing it is you were to have someone other than GM install the valve body kit, it would very difficult for a GM tech to even notice a difference in the valve body. GM techs would rarely disassemble the valve body, they would perform a direct exchange. Seems that the valve body problems are VERY prevalent and it is part of the design. Not sure what the newer valve bodies will have different that may help these problems. The metal seperator plate with the paper gasket appears to be a major internal leak point for the valve body, probably due to the difference in expansion and contraction between the aluminum valve body and the steel seperator plate. I am pretty sure the NextGen kit eleminates the paper gasket and has a thicker seperator plate. I know on one of the RAM truck kits they have a much thicker aluminum seperator or spacer they offer for that application.

Valve body problems are nothing new since most transmissions have switched to aluminum over cast iron for the valve body. Valve body wear due to valve gouging has been a big issue alone with internal leaks around the seperator plates.

Good luck and let us know what happens, seems MANY people have been parked for 4-5+ weeks at this point, hopefully parts will be moving out soon.

No mil or other warning lights ever came on. Just felt the shuttering... The dealer here has given us a '24 Yukon XL with the 6.2 loaner and it drives much nicer and smoother than I ever had with our new one.

At this point I'm looking for GM to make things right, as they should have for a $100k+ truck. Also, I don't want to pay more out of pocket to fix their problem. If our warranty was nearly up I might risk voiding it but at this point I have a long way to go and feel that's worth it with this problem potentially/likely persisting.

I also hope/pray parts will be available soon!!!

 

[Doubeleive]

It was rough shifting on the way home from the dealer, particularly while just cruising and feathering the throttle at or around 25-35mph. Also, pulling away from stop signs or lights. The easier we were on the throttle, the worse the shutter was.

We've been told that installing 3rd party parts will void the warranty. I'd like them to fix it, just sooner rather than later is the gamble were playing with here.

it is rare that gm actually replaces a transmission part, usually if say there was any kind metal found in there they would just slap a reman in it with a 3yr 100k warranty and send you on the way. that being said if you had 3rd party parts installed it's unlikely they would ever even know about it unless you opened your mouth and inserted foot.
being that it is currently a known specific issue with the valve body it is the only reason they are opening it up and replacing anything.
It would be a freak accident if they actually tore down a transmission and found any 3rd party part in there, there too lazy for that in almost all cases
the only thing they might actually rebuild at the dealer is differentials, if it was a seal leaking or something basic that they can do quick and easy.
normally they will just r&r stuff unless you are paying out of pocket and request a rebuild of "whatever" even then it's limited to certain things and it may even get farmed out to a 3rd party shop, like head resurfacing, etc

 

[jerry455]

I just had a new trans installed at my Chevrolet dealer. I bought a used, 70,000 miles, 2021 Suburban High Country 4WD last May. Last November my truck started to shift funny. I installed a new trans filter and fluid in the truck over Christmas. I didn't really help. Fluid was a little dark but not burnt. End of January it started to hesitate and search for gear. It was debating about a trans repair shop or Chevy dealer where I bought it. They inspected fluid and said it was burned and had metal in it. They put a new trans in it for $5,017. It works perfect now. They had it a month and after a week they asked if I wanted a courtesy car. They gave me a brand new 2025 Blazer. Not the same as my Suburban but I was impressed that they were trying to help. It did not have any light on just erratic and slipping shifts. I don't know the history of my truck before I owned it. I have replaced every other fluid and will continue to replace fluids religously. I love the truck and hope to drive it forever. I put almost 10,000 miles on the truck from purchase to trans replacement. It drives fantastic and pulls my travel trailer extremely well. I originally thought to take it to the dealer after seeing all of the bulletins about the 10 speed trans.

 

[jfoj]

@jerry455

Thanks for the comments and your experience.

Likely your transmission suffered from valve body problems like all these other trucks and with the mileage and use the valve body problems likely caused accelerated wear on the clutch packs.

The think you need to be careful and aware of is the valve body in the reman transmission that the dealer installed will likely suffer from some of the same probems your original exhibited. So pay careful attention to any shifting problems and get on top of it immediately.

Once the valve body wears and has internal pressure leaks the clutch packs suffer pretty quickly.

You may want to consider filling out a NHTSA complaint form to at least indicate the transmission started shifting hard and the transmission failed at a fairly early mileage. My 2005 Yukon 4 speed has 275,000 miles and still going strong.

 

[Staceyr72]

Update, Brought that bulletin release to my dealership, dated Dec, 13, 2024- last week, shameful, that I have to do my own research, and go in with proof, and ask for the biggest boss- still took them until today to give me a vehicle to drive, a 2025 Silverado, not very comparable to a high country Tahoe, but at least a vehicle to drive, and not at my expense, but however, my truck has been sitting there since January, and Chevy again emails me just yesterday- still no fix, no parts, and my truck does not qualify for their repurchase program, but they will keep me updated on the part- how sweet of them- and they did offer me $3000 to help trade my truck for the inconvenience, they must be crazy, I owe $54K, not my fault it's their problem and I won't carry a penny!

 

[Staceyr72]

I have a 2023 Yukon xl with the Duramax diesel and just had the valve body replaced a month ago at around 34500 miles. Took a few days to get the part.

You are fortunate
You have a 2023 and a diesel

This valve body issue is on the 2021 Tahoe which mine is unfortunately

 

[jfoj]

@Staceyr72

Glad you have something to drive for the short term.

Just so you are aware, only 2022 and earlier trucks/SUV's have had the software recall and valve body warranty extension at this point, ALL the 10 speed valve bodies are effectively the same with the same problem. The later model 2023+ trucks/SUV's will be recalled at some point and the valve bodies will have the warranty extended. We are starting to see 2023-2025 trucks/SUV's having problems at this point, some with fairly low mileage.

BUT EVERYONE with a 2023+ model Truck/SUV that has had valve body problems NEEDS to fill out out a NHTSA Complaint for the valve body problems to hopefully get enough traction for the NHTSA to conduct an investigation into ALL the 10 speed valve body problems. This will help everyone with a 10 speed automatic

NHTSA Complaint Form

After more and more research on this issue over the past few weeks, I plan on pulling my valvebody and reworking it myself before the end of the Summer. I have about 5500 miles on my 2024 Yukon at the moment and realize it is not IF, but WHEN the problem will occur. Luckily for me, this is something I can do and it will take me about 3 hours to do in the driveway.

I understand that it may be covered under warranty, but I do not want to even deal with this problem catching up with me when I do not expect it. I will proactively address the problem. I will pay out of pocket for this on my own and do the work myself. While valve bodies are not available at the moment, they will at some point be avaiable, but I do not want or need a GM remanufactured valve body that may still have some of the problems even if they "upgrade" them.

I hope you can get a valve body soon, but I know for me personally, I would wait no more than 2 weeks before I would be taking care of the problem for myself. Because this is how I am and I am able to do this repair. While I would not want to have to spend the money, I will do it in a heartbeat to get back on the road and move on. I have done many transmission repairs before and I have no issue dealing with a valve body rework with the correct, updated parts.

Edited to correct about Diesel and model year, I had some partial info that I was originally working from.

 

[Staceyr72]

@Staceyr72

Glad you have something to drive for the short term.

Just so you are aware, while ONLY the Diesel trucks have had the software recall and valve body warranty extension at this point, ALL the 10 speed valve bodies are effectively the same with the same problem. The gasoline trucks will be recalled at some point and the valve bodies will have the warranty extended.

BUT EVERYONE with a gasoline Truck/SUV that has had valve body problems NEEDS to fill out out a NHTSA Complaint for the valve body problems to hopefully get enough traction for the NHTSA to conduct an investigation into ALL the 10 speed valve body problems. This will help everyone with a 10 speed automatic

NHTSA Complaint Form

After more and more research on this issue over the past few weeks, I plan on pulling my valvebody and reworking it myself before the end of the Summer. I have about 5500 miles on my 2024 Yukon at the moment and realize it is not IF, but WHEN the problem will occur. Luckily for me, this is something I can do and it will take me about 3 hours to do in the driveway.

I understand that it may be covered under warranty, but I do not want to even deal with this problem catching up with me when I do not expect it. I will proactively address the problem. I will pay out of pocket for this on my own and do the work myself. While valve bodies are not available at the moment, they will at some point be avaiable, but I do not want or need a GM remanufactured valve body that may still have some of the problems even if they "upgrade" them.

I hope you can get a valve body soon, but I know for me personally, I would wait no more than 2 weeks before I would be taking care of the problem for myself. Because this is how I am and I am able to do this repair. While I would not want to have to spend the money, I will do it in a heartbeat to get back on the road and move on. I have done many transmission repairs before and I have no issue dealing with a valve body rework with the correct, updated parts.

Thank you so much for the info, I am defiantly taking this as far as I can go, and will fill out that form too. Did you see this document released Dec 13, 2024? They did their stupid reprograming on my truck January I had it 1 day. And my truck has been there ever since. I will not accept a rebuilt or remanufactured part. They will provide NEW or replace my transmission or give me a new truck and what I owe $54K. There are other companies in America that make this part and GM is going to have to make a sacrifice!

 

[Staceyr72]

Thank you so much for the info, I am defiantly taking this as far as I can go, and will fill out that form too. Did you see this document released Dec 13, 2024? They did their stupid reprograming on my truck January I had it 1 day. And my truck has been there ever since. I will not accept a rebuilt or remanufactured part. They will provide NEW or replace my transmission or give me a new truck and what I owe $54K. There are other companies in America that make this part and GM is going to have to make a sacrifice!

https://static.nhtsa.gov/odi/tsbs/2024/MC-11011826-0001.pdf

 

[Staceyr72]

Thank you so much for the info, I am defiantly taking this as far as I can go, and will fill out that form too. Did you see this document released Dec 13, 2024? They did their stupid reprograming on my truck January I had it 1 day. And my truck has been there ever since. I will not accept a rebuilt or remanufactured part. They will provide NEW or replace my transmission or give me a new truck and what I owe $54K. There are other companies in America that make this part and GM is going to have to make a sacrifice!

BTW great are you in Syracuse NY? LOL, Because That document also states chevy will reimburse repairs

 

[jfoj]

Do not hold your breath for a "new" valve body or transmission. GM and all the other manufacturers typically offer "factory" rebuilds. Even if you look up the current valve body part number, it is an "exchange" part.

I doubt there are many companies making this part as a "new" unit. Rebuilt or reworked valve bodies are nothing new, this has been going on for 50+ years.

 

[jfoj]

I went ahead an ordered the Project Carbon Valve Body kit with the 6 Shift Valves and plan on reworking my valve body as a preventative measure. I have determined the problem is not IF, but WHEN.

Will be trying to update my thread here with progress:

Project Carbon Valve Body

 

[Snefferz]

I'm so curious to how many 2021 Tahoes are having this issue?
I have a high country, 2021, my dealership has had it for over 2 months, can't get the part to fix it - valve body-
They have another one there, that's been there for 5 months, can't get the part.
So, 2 Tahoes at same dealership, same problem, and can't get the part to fix.
I have escalated to chevy, have a case number, chevy themselves can't get the part to fix my truck. But I still have to pay for it-big payment for something, I can't drive, isn't worth anything for trade and useless- I am furious. I have been a lifetime chevy owner-and this is changing my mind.

Last nights communication with chevy escalation please read:
Dear STACEY,

We have the following update for your 2021 Chevrolet Tahoe, case number 9-14734770575.

We are still experiencing a delay on the part(s) needed to repair your 2021 Chevrolet Tahoe. We understand this is a significant inconvenience and we continue to work diligently to resolve the delay. If further information is made available, you will be contacted by your dealer or myself. Thank you again for your patience and please contact me to discuss any additional questions or concerns you may have.

I can be reached at the number listed below or emailed at [email protected] (please reply with history to this email for fastest response).

AND MY RESPONSE:

​

Thank you for the update.
However Janet, if you can not find the part. I want my truck fixed asap. If that means a new transmission then that means a new transmission. This is a Chevy problem and Chevy knows it. Otherwise, payoff my truck. Give me full value so I can trade it I owe $54k.
Not to be a complete rude person. But if my truck doesn’t get fixed fast. I’m going to start escalating this to who ever will listen
I know this isn’t your fault. But it’s not mine either. And I have a $1300 a month payment for something I can’t drive. And Chevy can’t fix!

I’m in the same boat. I have a 2021 Yukon slt diesel. My transmission valve body is going out. My car kicks into gear. Took me 2 months to even get an appointment at the dealership. Now they’ve told me it’s on back order and I will probably be waiting all summer. I complained to the manager that I cannot be without a car. So frustrating!!