Valve Body Replacement - 2023 Silverado Custom Trail Boss

[66ss3964spd]

I haven't read of anyone here that knows what is failing in the VB, but I have to guess GM engineering has done the forensics and knows what fails. If they do know they aren't making it public knowledge, natch. We do know the original VB P/N has been superseded by at least one new P/N.

 

The 10 speed VB has a bunch of solenoids, and associated rods/plungers and springs. Probably a check ball or two. If any of them don't or can't go where the TCM tells them to, for whatever reason, failure.

[Michael Lung]

As the OG on this thread, first I’d like to start by saying I’m sorry for the people STILL getting dinged with this valve body issue. As far as for me, about 20K miles since the replacement and things are running as they should *knocks on wood*. I’m hoping things will last, but it’s just hard to tell with GM these days. 

[JustSomeDude]

16 hours ago, Michael Lung said:

As the OG on this thread, first I’d like to start by saying I’m sorry for the people STILL getting dinged with this valve body issue. As far as for me, about 20K miles since the replacement and things are running as they should *knocks on wood*. I’m hoping things will last, but it’s just hard to tell with GM these days. 

Thank you for posting the update.  I'm nervous about it.  I have not had much driving on the redone one yet.  I have only driven a little bit and I can't tell if Im being paranoid or if it is searching a little bit to get from 1st to 3rd.  I have some driving to do after work and will be trying to keep radio off and pay attention for any sounds and see how it feels under some different conditions.  Will not be towing anything today, but in a couple of days I will be pulling my trailer around for a little while.  

But to your point, it does stink that people are still getting hit with this issue. I'm still trying to get some word from GM rep as to what (if anything) they are going to do to help with the peace of mind.  

[Telum Pisces]

On 2/8/2025 at 3:23 PM, Telum Pisces said:

Does anyone know what is actually failing in these valve bodies?   They are pretty simple parts with channels and valves to direct all the fluid! The Ford version seems to have a different valve body in it and I can't seem to find the same or similar problems on the Ford version of this transmission!

 

Update!

Got my truck back today.  I will say that contacting GM directly and voicing your displeasure at the back ordered valve body with no ETA given from the dealer seamed to help my case!  The dealer was very surprised when a valve body showed up for my truck on Friday afternoon of last week.  Total time from problem to fixed was 1.5 weeks!  

Here's to hoping I don't have a repeat problem.  

Dealer had hopes that GM would eventually do a recall on these transmissions to actually fix them before people get stranded!

[66ss3964spd]

Glad you got yours back so quickly.

 

The "trigger" for my repair seemed to be when I opened a case with the BBB. I got a call from a different customer service organization within GM the very next day after I opened the BBB case. Evidently those BBB cases get routed differently and, it appears, GM jumps on them. Mine got fixed about a week later.

[JustSomeDude]

1 hour ago, Telum Pisces said:

Update!

Got my truck back today.  I will say that contacting GM directly and voicing your displeasure at the back ordered valve body with no ETA given from the dealer seamed to help my case!  The dealer was very surprised when a valve body showed up for my truck on Friday afternoon of last week.  Total time from problem to fixed was 1.5 weeks!  

Here's to hoping I don't have a repeat problem.  

Dealer had hopes that GM would eventually do a recall on these transmissions to actually fix them before people get stranded!

Good deal.  Squeaky wheel and grease and all that, but I seriously was trying to make sure that they knew there are more people with this issue than is reasonable for a reputable company to have. 

I did get to a GM rep today but didn't really love the needle for my comfort level/confidence that the truck is actually fixed. Referred me to local dealers technician who could be able to find more info about the VB that was put on. My ticket had the same part # listed as the one that went bad.  Still don't know if I'm dealing with a legit fixed one or got one that was still from the old batch. Will have to try to call the dealer tomorrow 

[Telum Pisces]

13 hours ago, JustSomeDude said:

Good deal.  Squeaky wheel and grease and all that, but I seriously was trying to make sure that they knew there are more people with this issue than is reasonable for a reputable company to have. 

I did get to a GM rep today but didn't really love the needle for my comfort level/confidence that the truck is actually fixed. Referred me to local dealers technician who could be able to find more info about the VB that was put on. My ticket had the same part # listed as the one that went bad.  Still don't know if I'm dealing with a legit fixed one or got one that was still from the old batch. Will have to try to call the dealer tomorrow 

My part number was different than the one in it.  I made sure of at least that.  But I don't know if that means anything!  It's going to take time for me to trust it.  Mine gave me no warning!  I didn't have hard shifts or anything!   I pulled out of a gas station and it just went out.   I had made it to 3rd or 4th gear and all of a sudden, no more gears at all.  Then it would only get to second and reverse was gone!  

Going to take a lot of time to pass for me to fully trust it.

 

[66ss3964spd]

Your symptoms sound exactly the same as mind did; no warning, pulled out of a gas station, drove maybe a couple hundred feet, then got a bunch of DIC warnings, wouldn't up shift past maybe 4th. Still had reverse though, I think.

 

While mine now seems fine complete trust is still 1000's of miles away.

[TBG]

I have a 2022 Chevy Trailboss bought in Oct 2022. I've got just under 30K on the 3.0L engine. On 1/31/25 I was getting on the highway and the transmission shifted very sluggish and got a check engine light. Got it to the dealer and found out today it's the transmission valve body. Part is suppose to be in dealers hands next week. We'll see.

[Bobby Nicholl]

Hey, First time poster, 2nd time valve body cracker. First time my 2021 Trail Boss 6.2L had 60k on it. Now a couple weeks ago, it went again with 90k on it. Part has no ETA. Got a fully loaded 2024 AT4 for a loaner, so i am not worried about when i get it back. BUT, i only have 10k left to go before my warranty runs out. It will happen a 3rd time, due to the part construction material has not changed. Does a guy, trade it in and buy a new GM or should a guy cut their losses and switch brands? I see 2024's are having the same issue. Anyone know if the construction material changed for the 2025's or a redesign of some sort?

 

Thanks  

[SilveradoRST]

2 hours ago, Bobby Nicholl said:

Hey, First time poster, 2nd time valve body cracker. First time my 2021 Trail Boss 6.2L had 60k on it. Now a couple weeks ago, it went again with 90k on it. Part has no ETA. Got a fully loaded 2024 AT4 for a loaner, so i am not worried about when i get it back. BUT, i only have 10k left to go before my warranty runs out. It will happen a 3rd time, due to the part construction material has not changed. Does a guy, trade it in and buy a new GM or should a guy cut their losses and switch brands? I see 2024's are having the same issue. Anyone know if the construction material changed for the 2025's or a redesign of some sort?

 

Thanks  

I’d like to know is it poor material quality or design spec?  

[Bobby Nicholl]

What I was told by a "service advisor" my first go around, was that it used to be made from a stronger material and now the new material keeps cracking or breaking. What that material is or if this is indeed the case I don't know. Metal to plastic maybe. No idea, but the first time this happened she was hoping GM would come up with a fix and issue a recall, but I see that has yet to happen. 

[Tom73]

On 2/9/2025 at 6:40 AM, Dan H 2023 HC said:

I haven't read of anyone here that knows what is failing in the VB, but I have to guess GM engineering has done the forensics and knows what fails. If they do know they aren't making it public knowledge, natch. We do know the original VB P/N has been superseded by at least one new P/N.

 

The 10 speed VB has a bunch of solenoids, and associated rods/plungers and springs. Probably a check ball or two. If any of them don't or can't go where the TCM tells them to, for whatever reason, failure.

I was told that it was the reverse solenoid in the valve body that went out. Said they do not replace solenoids in the valve body. They could not get a valve body so ended up with a new transmission. 

[66ss3964spd]

Doesn't appear that anyone outside of GM knows what the failure point in the valve body is, and there might be multiple failure points. Many people in this thread reported losing reverse but mine didn't.

 

Interesting that GM couldn't find a VB for yours, but could find an entire transmission. How long was your truck out of service?

[Bobby Nicholl]

I lost reverse both times. First time I got a tow. The second time I drove it to the dealership in limp mode hoping to crater the thing. Been there almost 2 weeks. No word or eta on part yet.