Transmission valve body-no parts to be found

[jfoj]

Bought the 2024 because I didn't want that horrendous big screen at the 2025 has. The only benefit that I see of the 2025 is the gauges will give you a numeric as well as a bar graph display and it also provides oil temperature. But I'm not sure it's really easy to display. 2025 actual instrument cluster the smaller than the earlier ones at least to me.

 

[2024 White Tahoe]

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!

https://gmauthority.com/blog/2025/08/next-gen-gm-valve-body-now-arriving-at-dealers/

 

[2024 White Tahoe]

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!

https://gmauthority.com/blog/2025/09/gen-3-gm-valve-body-our-exclusive-details-part-numbers-more/

 

[jfoj]

I guess it just goes to show you how bad these valve bodies are. With all the failures, recalls and software updates, GM is now on to its 3rd version valve body. But have they really decided to properly correct all the problems??

I guess only time will tell.

Glad I proactively upgraded my valve body with the Next Gen kit before I was left stranded.

The shift quality improvement with the Next Gen kit was quite obvious. So far I have about 2,000 miles since installing the Next Gen kit and things are working quite well.

Would be interesting to hear from someone that gets a new version 3 valve body if they feel the shift quality is significantly improved.

 

[jerry455]

I am not sure what would be in my new trans that was dealer installed last March.

 

[jfoj]

@jerry455

Unfortunately a dealer installed transmission that was installed last March would not likely have any updates to the valve body.

There was an earlier version of the GM 10 speed considered a Gen 1 that was released around 2017 and ran up to around 2019, then GM switched to a Gen 2 10 speed.

The "Gen 1" 10 speed valve body was quite a bit different than the "Gen 2" 10 speed first valve body.

I believe this talk about being on to the Gen 1-3 10 speed valve body is with valve bodies from 2019 forward. I do not believe GM had the high failure rate with the 2017-2019 series transmission, but there were problems.

This is all somewhat of a moving target and until someone in the aftermarket gets their hands on a "Gen 3" 10 speed valve body to see what GM has improved, I would expect there to still be some future problems.

I do know that recently GM released a steel valve upgrade for 1 specific valve in the 10 Speed "Allison" or 10L1000 version transmissions, and this is likely the first valve upgrade in years that GM has actually released rather than exchanging valve bodies.

 

[Joe_A]

Seems I've joined the club!

2023 Yukon SLT with 48K miles . . .

PO 0747 - Solenoid Valve 1 Stuck On

About three weeks ago the truck hesitated during slow, local driving . . . and with a message similar to "Reduced Acceleration - Drive with Caution"

The selling dealer had it for a few days. As I picked it up after hours, I did not have an opportunity to find out what action they took that temporarily cleared the issue. I still do not know, but nothing fixes itself.

After about a week, the truck bucked a little, shifted a bit erratically, and then PO 0747 returned.

I'm new here having found this place as a result of searching for info about the issue. I shall return with any experience I may have that may be helpful.

Cheers,

~ Joe

Aside: Coincidentally I had recently purchased a bidirectional VCX FD diagnostic tool from VXDIAG with their somewhat dodgy software, but I had not set it up until after the issue showed up. The software runs either Tech2 Win or GDS2 as needed depending upon age of vehicle.

 

[jfoj]

Good luck, I guess you could give the dealer a chance to perform the repair, however, the question is how long will parts take to get and they will likely have the Version 3 valve body or a rebuilt version 2 to install. If the repair will be covered under Warranty, you could go for it, if the issue is a customer pay job, I would upgrade the valve body with the Next Gen kit.

The issue is at the end of the day, nothing GM has to offer is a permanent fix.

I have a buddy that just bought a 2026 3500 series 6.6 gas pickup and it does not have the "Real" Allison transmission it has a 10L1000. He has about 400 miles on it and he is already planning to install the Next Gen valve body upgrade.

 

[Joe_A]

Good luck, I guess you could give the dealer a chance to perform the repair, however, the question is how long will parts take to get and they will likely have the Version 3 valve body or a rebuilt version 2 to install. If the repair will be covered under Warranty, you could go for it, if the issue is a customer pay job, I would upgrade the valve body with the Next Gen kit.

The issue is at the end of the day, nothing GM has to offer is a permanent fix.

I have a buddy that just bought a 2026 3500 series 6.6 gas pickup and it does not have the "Real" Allison transmission it has a 10L1000. He has about 400 miles on it and he is already planning to install the Next Gen valve body upgrade.

Thanks!

The work, such that it may be, will be covered under warranty, otherwise I would go for the Next Gen kit.

I only found this place yesterday and I read through a few threads as well as having followed the link to Next Gen.

It's a bit hard to accept that one engineer knows more than a group of engineers about what is wrong with the valve body and what needs to be done to redesign it. It's more likely that the engineers haven't been given the budget for a redesign. A smaller independent entrepreneur can be a lot more flexible than a major corporation that is looking at millions in liability to correct the issue.

I did file with the NHSTA as recommended here.

I'll report on relevant progress.

 

[jfoj]

It's all about being cheap, design down to a price not to a level of performance and reliability!