Transmission Valve Unit issues?

[8x68]

Hello everyone,

I have a 2022 Sierra AT4 that in the last few weeks has given me a message of Warning! Reduced acceleration. Drive with care.
At that point the truck seems to rev slightly higher than normal and does not shift past a certain gear. As the revs are slightly higher shifting between P, N, R, and D is a touch jerky. You can restart the truck and the issue goes away.
Took it to the dealership and after a couple of days I got told that it is apparently an issue with the Transmission Valve Unit.
The issue is that apparently there are no spare parts available in Canada or the US at the moment. Time to get it fixed is unknown.
Has anyone experienced this issue?
I need this truck for work and I’ve heard horror stories about people not having their truck for several months.

Any insight and advice how to address this with GM would be immensely appreciated.

 

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[Island Dan]

Sounds like you're up the creek. If there are no parts available there isn't anything your dealer can do about it. Good thing is that you reported it, the dealer diagnosed it and you have a temporary work around to reset it (restarting the truck). So if it does take a giant shit before the parts are available, your covered. Just gotta have a game plan if that happens. Welcome to modern vehicle ownership.

 

[Kylewal78]

My truck is doing the exact same thing and the dealer told me it’s back ordered so I’m truckless right now. I could turn mine off and back on and it would last all of about 1-2 mins before it did it again

 

[gemarsh]

My truck is doing the exact same thing and the dealer told me it’s back ordered so I’m truckless right now. I could turn mine off and back on and it would last all of about 1-2 mins before it did it again

Welcome.

 

[8x68]

Googling it further it appears to be quite a common issue and a few people are getting the entire transmission replaced. This is really disheartening.

 

[jgaestel]

Hello everyone,

I have a 2022 Sierra AT4 that in the last few weeks has given me a message of Warning! Reduced acceleration. Drive with care.
At that point the truck seems to rev slightly higher than normal and does not shift past a certain gear. As the revs are slightly higher shifting between P, N, R, and D is a touch jerky. You can restart the truck and the issue goes away.
Took it to the dealership and after a couple of days I got told that it is apparently an issue with the Transmission Valve Unit.
The issue is that apparently there are no spare parts available in Canada or the US at the moment. Time to get it fixed is unknown.
Has anyone experienced this issue?
I need this truck for work and I’ve heard horror stories about people not having their truck for several months.

Any insight and advice how to address this with GM would be immensely appreciated.

My AT4 2500 is in the shop as we speak. The preliminary diagnosis was possible valve body. My code was for the pressure control solenoid A stuck open code P0747 and P0700 Transmission Control System. The inspection is not complete until Monday. I will advise. But if that is the case it could be a four month wait for parts.

 

[8x68]

Well, the dilemma is over. Got my truck back a couple of weeks ago after 6 weeks of being in the shop. I was lucky to have a great service rep who advocated for its repair, and I was relentless in calling GM every 3 days or so and speaking to a CSR. I also asked to be transferred to GM Financial and explained the situation. I called GM Financial a couple of weeks later, mentioning that I was stopping all monthly payments immediately until I got my truck back, and if I did not receive the truck back within the next 2 weeks, I was going to begin the process to get a refund for my truck, as obviously G< was still producing trucks every day, so the parts were available, just not available for my truck.
Well, low and behold, in that same call, I got notified that it looked like a part was already being shipped for my truck and should be ready in the next few days.
Coincidentally, an hour later, my CSR called me to say the same thing.

I would say the coincidence between my last call and the part being available is uncanny.

 

[Chicks90]

Hello everyone,

I have a 2022 Sierra AT4 that in the last few weeks has given me a message of Warning! Reduced acceleration. Drive with care.
At that point the truck seems to rev slightly higher than normal and does not shift past a certain gear. As the revs are slightly higher shifting between P, N, R, and D is a touch jerky. You can restart the truck and the issue goes away.
Took it to the dealership and after a couple of days I got told that it is apparently an issue with the Transmission Valve Unit.
The issue is that apparently there are no spare parts available in Canada or the US at the moment. Time to get it fixed is unknown.
Has anyone experienced this issue?
I need this truck for work and I’ve heard horror stories about people not having their truck for several months.

Any insight and advice how to address this with GM would be immensely appreciated.

Dealing with the exact same issue right now, dealer has had mine for going on 3 weeks. No eta on parts, meanwhile they have 100 new sierras on the lot just sitting.

 

[jgaestel]

Hi everyone, I have 23 Sierra 2500 AT4 with 42000 miles on it. The dealership just told me that the transmission valve body has failed and needs to be replaced. The truck is in the shop and parts are on national back order with a possible delay of at least two months, maybe more. Due to this delay, I wound up CarMax about the problem, and to my surprise they are willing to buy the truck back, as I am withing their 90-warranty period. Through CM I found a similar Sierra 2500 AT4 truck without some of the options but mostly the same with 10000 miles. So do I keep the original AT4 with 42k and a fixed transmission or to I do the buy back with the other 23 AT4 with 10k miles on it. Should I worry about it's transmission? Suggestions?

 

[R467X]

Hi everyone, I have 23 Sierra 2500 AT4 with 42000 miles on it. The dealership just told me that the transmission valve body has failed and needs to be replaced. The truck is in the shop and parts are on national back order with a possible delay of at least two months, maybe more. Due to this delay, I wound up CarMax about the problem, and to my surprise they are willing to buy the truck back, as I am withing their 90-warranty period. Through CM I found a similar Sierra 2500 AT4 truck without some of the options but mostly the same with 10000 miles. So do I keep the original AT4 with 42k and a fixed transmission or to I do the buy back with the other 23 AT4 with 10k miles on it. Should I worry about it's transmission? Suggestions?

I would keep it. No guarantees your new truck won't experience the same issue down the line. Or have other issues. I don't trust used diesels unless I know the owner and know the truck was treated well, being allowed to Regen properly, fuel additives used every fill up, not used to idle around all the time etc

Unless you upgrade to a 24. Haven't heard of any knock on wood 24's with this issue. Maybe GM replaced something when producing them. I sense a recall coming out eventually.

 

[jgaestel]

Thanks for the input. You read my mind on the transmission issues. How prevalent is the problem? My service writer stated that he has similar valve body failures at half my mileage, so given that I was leaning towards keeping the truck even though there is going to be a wait on getting the truck fixed. Or I sell it back to CarMax and get a used F250 or even a F150 with max tow package as my trailer is not that heavy. I guess I am getting cheap in my old age.

 

[R467X]

Thanks for the input. You read my mind on the transmission issues. How prevalent is the problem? My service writer stated that he has similar valve body failures at half my mileage, so given that I was leaning towards keeping the truck even though there is going to be a wait on getting the truck fixed. Or I sell it back to CarMax and get a used F250 or even a F150 with max tow package as my trailer is not that heavy. I guess I am getting cheap in my old age.

I wouldn't call it wide spread from what I've seen but it is out there enough to be noticed. It appears to be happening on more higher mileage vehicles than super low miles. Couldn't point specifically what triggers it either. I also don't know how those people with 75k+ miles maintain their vehicles. Do they change their trans fluid frequently since they RV full time? No idea. This shouldn't happen period on a Duramax but nothing is perfect anymore. Even Toyota has gone down the pipe with their latest EPA friendly trash power plant.

I was also looking at an equivalent Ford before I pulled the trigger on my at4 HD. Ford's power stroke has very prevalent CP4 pump issues. When it grenades, your entire fuel system is gone with it. If you get one, there are a few aftermarket saver options I'd get done the moment you buy one.

I haven't sold my 11 suburban because unfortunately in today's age, you can't expect your brand new rig to be perfect. So my advise would be to buy a cheap higher mileage truck. I'm GM biased so I'd get a 6.0 gas powered truck to have around in instances similar to this. Super easy to work on especially if you stay at 2014 tops. I recently did an AFM + VVT delete on my 5.3 suburban. Plenty of aftermarket options and lots of videos out there on how to fix just about anything. Parts are cheap too.

 

[NOMOREGM4ME]

I wouldn't call it wide spread from what I've seen but it is out there enough to be noticed. It appears to be happening on more higher mileage vehicles than super low miles. Couldn't point specifically what triggers it either. I also don't know how those people with 75k+ miles maintain their vehicles. Do they change their trans fluid frequently since they RV full time? No idea. This shouldn't happen period on a Duramax but nothing is perfect anymore. Even Toyota has gone down the pipe with their latest EPA friendly trash power plant.

I was also looking at an equivalent Ford before I pulled the trigger on my at4 HD. Ford's power stroke has very prevalent CP4 pump issues. When it grenades, your entire fuel system is gone with it. If you get one, there are a few aftermarket saver options I'd get done the moment you buy one.

I haven't sold my 11 suburban because unfortunately in today's age, you can't expect your brand new rig to be perfect. So my advise would be to buy a cheap higher mileage truck. I'm GM biased so I'd get a 6.0 gas powered truck to have around in instances similar to this. Super easy to work on especially if you stay at 2014 tops. I recently did an AFM + VVT delete on my 5.3 suburban. Plenty of aftermarket options and lots of videos out there on how to fix just about anything. Parts are cheap too.

I have a 23 3.0L with 26k miles. Never towed and baby the truck. Just dropped it off at the dealership yesterday and this was the diagnoses. They said it’s happening a lot right now and I may have to wait up to 3 months to get it fixed.
Talked to GM today about them reimbursing my monthly payment and they said they would do it.

 

[NOMOREGM4ME]

Hello everyone,

I have a 2022 Sierra AT4 that in the last few weeks has given me a message of Warning! Reduced acceleration. Drive with care.
At that point the truck seems to rev slightly higher than normal and does not shift past a certain gear. As the revs are slightly higher shifting between P, N, R, and D is a touch jerky. You can restart the truck and the issue goes away.
Took it to the dealership and after a couple of days I got told that it is apparently an issue with the Transmission Valve Unit.
The issue is that apparently there are no spare parts available in Canada or the US at the moment. Time to get it fixed is unknown.
Has anyone experienced this issue?
I need this truck for work and I’ve heard horror stories about people not having their truck for several months.

Any insight and advice how to address this with GM would be immensely appreciated.

Just happened to my 23 3.0L with 26k miles. Bought it new and truck has been babied. This is my business vehicle so now I’m out a truck for up to 3 months. All the dealership is offering is some small rental. There has to be a better option for GM then shelling out all this cash to have trucks sitting around dealership lots waiting on a new part.

 

[gemarsh]

I have a 23 3.0L with 26k miles. Never towed and baby the truck. Just dropped it off at the dealership yesterday and this was the diagnoses. They said it’s happening a lot right now and I may have to wait up to 3 months to get it fixed.
Talked to GM today about them reimbursing my monthly payment and they said they would do it.

Welcome.