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Posted

Parts are probably in a container on a ship in Baltimore harbor. 

Posted
On 5/6/2024 at 6:58 PM, Bikerjon said:

This has been reported on here more often. Others are being told the same sh*t. Back ordered and they don't know when the part will cone in.

I had a valve body put in last week and the same sh*t is still happening. Mine is a 23 2500 Denali.  I waited a few years for this new transmission to work out the bugs before I bought one. Evidently money is more important to them than we are . Keep building them and deal with the problems as they arise.  Pretty poor business model.  I digress.

so the way I see it , every vehicle is just a computer with wheels, so they should be able to run a diagnostic on it and see the problem even without an active code . Imo

Posted
On 5/14/2024 at 1:35 PM, Shannon23denali said:

I had a valve body put in last week and the same sh*t is still happening. Mine is a 23 2500 Denali.  I waited a few years for this new transmission to work out the bugs before I bought one. Evidently money is more important to them than we are . Keep building them and deal with the problems as they arise.  Pretty poor business model.  I digress.

so the way I see it , every vehicle is just a computer with wheels, so they should be able to run a diagnostic on it and see the problem even without an active code . Imo

We regret to hear that you are experiencing ongoing concerns with your vehicle and would like to investigate this further for you. Please send us an email to [email protected]. Be sure to include your Username and Forum name in the subject line with additional details. We look forward to your email. 

Posted

My 2023 3500 HD Sierra transmission just failed with less than 16,000 miles on it. When mine attempted to shift out of first gear the truck shook like I had ran over a speed bump, dash flashed reduce power limit and check engine light come on. 3 hours from home. When I final got ahold of the Dealership they state valve body needed to be replaced and they have no ideal when they would get the part to repair it. Had to get rental car to continue my trip. This is my 5th GMC/Chevy 3500 HD and probably my last. For 90,000 dollars you would think care of you or atleast try.

Posted
On 5/1/2024 at 9:58 PM, 4x4Hank said:

It sounds very similar to the very problematic GM 8spd transmission symptoms. 

As someone that had two GM vehicles with the dreaded A8 shudder, yes! It sounds very similar indeed. ☹️

Posted

Hi 

I have the same transmission problem (10 speeds and 3.0L diesel, AT4). I left the dealership this afternoon and they were not able to reproduce the problem. I have 11 000miles and I have symptoms since the first day. Some metallics noises are presents when shifting back into 1st gear and give a knock and hesitates in certain gear changes. The mecanic came with me to the road test and connected his computer. He said to me that the 10 speeds is capricious and that he didn’t adnormal sign in the road test. I’m so disapointed…

Posted

I just bought a 2023 GMC Sierra, V8 5.3L with 10-speed automatic transmission, last month. So far, drive 1000 miles, and find the same issue with the transmission. 

Posted
On 4/23/2024 at 8:38 PM, Edward J Smith said:

Yes I have the same thing going on with my 2024 sierra Denali I leased this truck in March and after 500 miles I noticed a vibration coming from the rear wheels and it felt like maybe a wheel weight came off so the dealer rebalanced all 4 wheels then rotated the wheels and this did nothing and then they showed me a GMC buliton that said some 10 speed transmission models may have a shutter thing going but GM is aware of this but you can try putting your shifter in L9 this will eliminate the AMF from working so you can see if that is your problem and this was not my problem at all I still have a shutter problem any where from 35 MPH up and I’m still complaining about it and now I have 3600 on it I will keep posting as time goes on 4/23/24

 

Posted
Just now, Edward J Smith said:

Up date for shaking 2024 siearra after complaining enough the service manager took my truck home for a good test drive and agreed there is a problem so she had a GM rep come and take it for a ride and agreed too so he said rebalance wheels again  and they were road force balance for a 2nd time and this time one tire failed so manager replaced the one tire and now shaking is gone 5/28/24

 

  • 2 weeks later...
Posted

I have a 2021 Sierra AT4 with the 10sp and 3.0l. It has 44K miles. Trans issues started end of April. After 8 CEL episodes with hard shifts/stutters and a couple episodes with multiple dash lights and reduced power mode I started a spread sheet that showed it was always 15 miles into a drive, 155* tranny temp, and going 48-52 MPH. Finally the dealer was able to diagnose it and determined it to be a bad valve body. I was told 6 mo back order but they got it in after 3 weeks. I picked it up saturday (3 days ago) and the exact same thing happened again today. Very upset to say the least.....

 

Whats the next step? I have also had a few exhaust sensors fail.

Posted
6 hours ago, BeWitty said:

I have a 2021 Sierra AT4 with the 10sp and 3.0l. It has 44K miles. Trans issues started end of April. After 8 CEL episodes with hard shifts/stutters and a couple episodes with multiple dash lights and reduced power mode I started a spread sheet that showed it was always 15 miles into a drive, 155* tranny temp, and going 48-52 MPH. Finally the dealer was able to diagnose it and determined it to be a bad valve body. I was told 6 mo back order but they got it in after 3 weeks. I picked it up saturday (3 days ago) and the exact same thing happened again today. Very upset to say the least.....

 

Whats the next step? I have also had a few exhaust sensors fail.

http://www.gm.com/privacy-statement.html Start a case with GM and keep us posted. I am also having trans shuddering problems with my truck. 5.3L -10 speed trans.

Posted (edited)

Before today the codes have always been P0700, P2826, and P2824. (9 times - 8 before new valve body, 1 after new VB)

 

Todays episode was different. I had multiple bad shifts and the check light didn't come on. About a minute after it slammed hard and I had multiple dash notification (service esc, reduced power, traction control off, service parking brake). I turned the truck off and waited a few minutes like I always do and restarted it and drove to work. I checked the codes when I got to work. Same 3 but I also got P1098 for the first time. Not sure what was different about this episode.

 

I am scheduled to drop my truck off at the dealership on Monday. I wont be driving this truck to work anymore this week, cant trust it. I believe there is a big issue with the transmission itself and it is causing the solenoids (valve body) to malfunction causing those to throw the codes? But the real problem is the tranny. I'm worried they are just going to replace the valve body again and i'll be doing this same thing in a month.

Edited by BeWitty
Posted

My 2023 2500 Silverado Diesel is sitting on a rack at my Chevy dealer for who knows how long due to a shift valve body that they can't tell me when they will ever see one. I'm outraged with GM! I see this is an ongoing issue by this and other blogs that they have no remedy in site. I paid over 80K for this truck expecting a reliable vehicle for the next few years. I switched from Ram to Chevy after years of buying new Rams every 3 years for my business. This is unacceptable for any car maker, whether its 20K or 80K. This convinced me that I need to go back to Ram. Chevy is not what it used to be. GM does NOT stand behind there product! If your thinking about a new GM product I would strongly advise you to read the blogs regarding all of the problems their having getting parts. Stay away from GM

  • Like 1
Posted (edited)

I bought my 2024 GMC Sierra 1500 diesel last August. 13,000km now. On June 8th was going on a fishing trip. 5 hours from home hard shift, reduced acceleration, check your engine light and a mile later truck stopped in the middle of hwy. Transmission oil all over my trailer. At the dealership said needs new transmission. Second week waiting, no end in sight. NEVER AGAIN GMC.

Wanted to update. It took3.5 weeks to replace transmission. Hoocked up my trailer and went again on a trip. Drove 1300km. Transmission is gone again.

Edited by Dmitri
Posted
25 minutes ago, Dmitri said:

I bought my 2024 GMC Sierra 1500 diesel last August. 13,000km now. On June 8th was going on a fishing trip. 5 hours from home hard shift, reduced acceleration, check your engine light and a mile later truck stopped in the middle of hwy. Transmission oil all over my trailer. At the dealership said needs new transmission. Second week waiting, no end in sight. NEVER AGAIN GMC.

 

Go visit the Ram and F-150 forums and you'll see similar posts.  Toyotas even have some problems too, but I don't think quite as bad

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