Just putting this initial info out about the Project Carbon Next Gen 10 Speed Valve body kit for anyone that wants to follow along.
I contacted Next Gen and spoke at length with the design Engineer that came up with the Project Carbon valve body repair/update. Spoke about many topics but it seems they have done their homework on this update and found many things about the OE valve body design and parts choices that are causing problems. They drew from experience from all the other transmissions they have repaired over the years and took what worked and lasted from other manufacturers and applied the materials and techniques to the GM OE valve body.
Mostly it comes down to higher quality machined steel spool valves that are properly chamfered and highly polished, one piece thicker laser cut valve body separator plates without the need for paper gaskets that can fail and getting rid of the steel, not even stainless steel, filter screens that tend to tear and end up with steel wires from the screens getting caught up in the magnetic control solenoids and/or jamming spool valves in the valve body. They also have some modifications for the lube circuits as well as some other precision machined steel valves with O-rings that will not wear the valve body bores like the standard poorly machines aluminum valves in the OE valve body.
I put the Next Gen representative on the spot a bit about how many of these valve body kits they have sold and he is more on the Technical side and not the Sales side, but he said in the range of 4000-5000 kits.
I decided to Preventatively and Proactively purchase the full Project Carbon valve body upgrade kit with the addition of the billet shift valves, which are not cheap, and the total with shipping came out to around $1500.
Some people may say why am I doing this. Part of the reason is I have built automatic transmissions in the past, modified valve bodies and dealt with similar valve body problems so I understand what this kit changes, upgrades or modifies. I also understand how the valve body bores can wear over time with aluminum valves riding in aluminum valve body bores. The other issue is what happens when the valve body starts to have internal leaks and/or valve body bore wear, the application of the clutch packs is impacted and the clutch packs can start slipping and cause more advanced wear in the transmission. Some may not be able to detect some of the slippage, but you will clearly feel harsh or banging during shifting. Since these transmissions are pretty smooth shifting even of you are the daily driver and are trying to be aware of any change in shift slippage, you may not notice problems until additional clutch pack wear has occurred.
My goal is to head off any serious transmission clutch wear. While the 2023+ light trucks have not been recalled, I expect they will based on a lot of searching I have done online and the failures I am even seeing even with some of the 2025 models. I would have assumed GM may have updated the transmission software on the 2025 models, but maybe they did not get it in the earlier builds. The Recall is only for a software update that DOES NOT CORRECT OR FIX the valve body problems. All the Recall does is update the transmission control module software to "detect" wear and slippage and to put the transmission in a "Limp" mode that will not allow the transmission to shift above 5th gear, limiting the vehicle to about 45 MPH. As part of the "Recall" if your VIN is covered, GM will extend the valve body and only the valve body warranty to 15 Years/150,000 miles. The rest of the transmission does not have the warranty extended and a faulty valve body can cause excessive wear or possible failure within the transmission. I think it is still too early to tell if the transmission software update can really "protect" the transmission from lower pressures applying clutch packs and premature transmission clutch pack wear.
I plan on personally pulling the valve body and installing the Project Carbon valve body update kit hopefully before my truck has 7500 miles on it. I will update this thread with pictures of the kit parts once received and try to get some pictures during the valve body upgrade and determine how difficult a job this will be. It is a bit more work and advanced than changing the transmission fluid, but I would hope that someone that could do brake work or replace a water pump could do this work. Next Gen says most people can do the job in about 3 hours in the driveway. You could also have a local transmission show install the parts probably for about 3 hours of labor and fluid locally if you do not think you could do the work yourself.
I do a lot of long haul trips and I would rather head off problems, even if I have to pay for it out of my own pocket. At the moment I am seeing too many stories of owners that have been held up for 2-4 months waiting on a GM rebuilt valve body that may not be much better than the the original the vehicle shipped with. I assume at some point the months long delays may get much shorter, but a valve body problem will at a minimum probably cause at least 3 days loss of the vehicle in most cases. Again, based on the searching I have been doing, I am seeing 2023-2025 models with these valve body problems, some with as few as 1,000 miles! I personally think this is a more "When" than "If" scenario. I do believe that the 2022-2025 models will likely be recalled based on the recent Cadillac and Camero recall.
I would rather take my chances spending my own money and time on what appears to be a superior set of parts to address the problem before it becomes a "problem".
Again, some may way why do this, you have a warranty, I say I do not want the hassle and potential for additional transmission clutch pack damage. I would rather have control over the repair in my driveway than at the dealer, this is just me. I have the skills, experience and tools to do this job, so it will get done depending on my schedule.
I have already done a lot of things to try and keep the 6.2l alive: DFM and Auto/Stop Start bypassed, Catch Can installed, Magnetic oil drain plug, no remote starting or allowing the truck to idle to warm up especially in the Winter, 3rd oil change before 6,000 miles, no 0W20 crap in the crankcase, running 9 quarts with oil filter.
So we shall see how things go, will try to add updates as I get parts and have time to perform the valve body upgrade.
Project Carbon Valve Body
Project Carbon Repair Story
As the world burns!
I contacted Next Gen and spoke at length with the design Engineer that came up with the Project Carbon valve body repair/update. Spoke about many topics but it seems they have done their homework on this update and found many things about the OE valve body design and parts choices that are causing problems. They drew from experience from all the other transmissions they have repaired over the years and took what worked and lasted from other manufacturers and applied the materials and techniques to the GM OE valve body.
Mostly it comes down to higher quality machined steel spool valves that are properly chamfered and highly polished, one piece thicker laser cut valve body separator plates without the need for paper gaskets that can fail and getting rid of the steel, not even stainless steel, filter screens that tend to tear and end up with steel wires from the screens getting caught up in the magnetic control solenoids and/or jamming spool valves in the valve body. They also have some modifications for the lube circuits as well as some other precision machined steel valves with O-rings that will not wear the valve body bores like the standard poorly machines aluminum valves in the OE valve body.
I put the Next Gen representative on the spot a bit about how many of these valve body kits they have sold and he is more on the Technical side and not the Sales side, but he said in the range of 4000-5000 kits.
I decided to Preventatively and Proactively purchase the full Project Carbon valve body upgrade kit with the addition of the billet shift valves, which are not cheap, and the total with shipping came out to around $1500.
Some people may say why am I doing this. Part of the reason is I have built automatic transmissions in the past, modified valve bodies and dealt with similar valve body problems so I understand what this kit changes, upgrades or modifies. I also understand how the valve body bores can wear over time with aluminum valves riding in aluminum valve body bores. The other issue is what happens when the valve body starts to have internal leaks and/or valve body bore wear, the application of the clutch packs is impacted and the clutch packs can start slipping and cause more advanced wear in the transmission. Some may not be able to detect some of the slippage, but you will clearly feel harsh or banging during shifting. Since these transmissions are pretty smooth shifting even of you are the daily driver and are trying to be aware of any change in shift slippage, you may not notice problems until additional clutch pack wear has occurred.
My goal is to head off any serious transmission clutch wear. While the 2023+ light trucks have not been recalled, I expect they will based on a lot of searching I have done online and the failures I am even seeing even with some of the 2025 models. I would have assumed GM may have updated the transmission software on the 2025 models, but maybe they did not get it in the earlier builds. The Recall is only for a software update that DOES NOT CORRECT OR FIX the valve body problems. All the Recall does is update the transmission control module software to "detect" wear and slippage and to put the transmission in a "Limp" mode that will not allow the transmission to shift above 5th gear, limiting the vehicle to about 45 MPH. As part of the "Recall" if your VIN is covered, GM will extend the valve body and only the valve body warranty to 15 Years/150,000 miles. The rest of the transmission does not have the warranty extended and a faulty valve body can cause excessive wear or possible failure within the transmission. I think it is still too early to tell if the transmission software update can really "protect" the transmission from lower pressures applying clutch packs and premature transmission clutch pack wear.
I plan on personally pulling the valve body and installing the Project Carbon valve body update kit hopefully before my truck has 7500 miles on it. I will update this thread with pictures of the kit parts once received and try to get some pictures during the valve body upgrade and determine how difficult a job this will be. It is a bit more work and advanced than changing the transmission fluid, but I would hope that someone that could do brake work or replace a water pump could do this work. Next Gen says most people can do the job in about 3 hours in the driveway. You could also have a local transmission show install the parts probably for about 3 hours of labor and fluid locally if you do not think you could do the work yourself.
I do a lot of long haul trips and I would rather head off problems, even if I have to pay for it out of my own pocket. At the moment I am seeing too many stories of owners that have been held up for 2-4 months waiting on a GM rebuilt valve body that may not be much better than the the original the vehicle shipped with. I assume at some point the months long delays may get much shorter, but a valve body problem will at a minimum probably cause at least 3 days loss of the vehicle in most cases. Again, based on the searching I have been doing, I am seeing 2023-2025 models with these valve body problems, some with as few as 1,000 miles! I personally think this is a more "When" than "If" scenario. I do believe that the 2022-2025 models will likely be recalled based on the recent Cadillac and Camero recall.
I would rather take my chances spending my own money and time on what appears to be a superior set of parts to address the problem before it becomes a "problem".
Again, some may way why do this, you have a warranty, I say I do not want the hassle and potential for additional transmission clutch pack damage. I would rather have control over the repair in my driveway than at the dealer, this is just me. I have the skills, experience and tools to do this job, so it will get done depending on my schedule.
I have already done a lot of things to try and keep the 6.2l alive: DFM and Auto/Stop Start bypassed, Catch Can installed, Magnetic oil drain plug, no remote starting or allowing the truck to idle to warm up especially in the Winter, 3rd oil change before 6,000 miles, no 0W20 crap in the crankcase, running 9 quarts with oil filter.
So we shall see how things go, will try to add updates as I get parts and have time to perform the valve body upgrade.
Project Carbon Valve Body
Project Carbon Repair Story
As the world burns!
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