A number of 2024 10 speed transmission failures with fairly low miles documented here.
2024 Transmission Failures
2024 Transmission Failures
Project Carbon Next Gen 10 Speed Valve Body Kit
- Thread starter jfoj
- Start date
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A few updates on arrivals. The Project Carbon valve body kit showed up yesterday, my ATSG transmission manual arrived today. So this pretty much completes the hunting and gathering process. Now to read over everything, check inventory and figure out between my schedule and the weather when I will have time to tackle the job.
Initial impression of the Project Carbon parts is they appear to be very high quality. The valve body separator plates appear to be made out of 14 gauge steel, 0.0747", 5/64" or 1.9 mm however you choose to look at the thickness. I expect this to be at least 2X the thickness of the OE separator plates. Understand that the hydraulic pressure in this area is probably in the range of around 250 PSI, so thickness matters.
I chose to order the 6 shift valves to hopefully head off excessive valve bore wear and leakage problems. There is no manual shift valve required or needed on vehicles with the "electronic" shifters, only earlier models with the shift cable requires the manual shift valve.
Overall nice machine work on the valves and instructions appear to be fairly straight forward and easy to follow. I will likely be making some notes on the instructions to make sure things are 100% clear when I am in the heat of the moment and I am getting interrupted every 15 minutes!
The only wildcard left will be adventures in fluid level checking. Unfortunately the ATSG manual has nothing useful about checking the fluid level. What I have found on the Interwebs, YouTube University and from other forums and even some of the GM bulletins nothing really agrees or makes since from the standpoint of not getting burned to hell with close to 200F transmission fluid. A lot of what I have found is just wrong. I have some ideas and will need to implement them on the fly and see how things go.
Now for some eye candy!
Initial impression of the Project Carbon parts is they appear to be very high quality. The valve body separator plates appear to be made out of 14 gauge steel, 0.0747", 5/64" or 1.9 mm however you choose to look at the thickness. I expect this to be at least 2X the thickness of the OE separator plates. Understand that the hydraulic pressure in this area is probably in the range of around 250 PSI, so thickness matters.
I chose to order the 6 shift valves to hopefully head off excessive valve bore wear and leakage problems. There is no manual shift valve required or needed on vehicles with the "electronic" shifters, only earlier models with the shift cable requires the manual shift valve.
Overall nice machine work on the valves and instructions appear to be fairly straight forward and easy to follow. I will likely be making some notes on the instructions to make sure things are 100% clear when I am in the heat of the moment and I am getting interrupted every 15 minutes!
The only wildcard left will be adventures in fluid level checking. Unfortunately the ATSG manual has nothing useful about checking the fluid level. What I have found on the Interwebs, YouTube University and from other forums and even some of the GM bulletins nothing really agrees or makes since from the standpoint of not getting burned to hell with close to 200F transmission fluid. A lot of what I have found is just wrong. I have some ideas and will need to implement them on the fly and see how things go.
Now for some eye candy!
viven44
Full Access Member
On another matter, I called my trusty local transmission shop in Plano TX that has been around since 1966. These old timers have been doing this for a LONG time.... While talking I asked them about the 10-speeds and apparently, they rebuild even these 10-speeds !! All new hard and soft parts (clutch, pistons, drums as needed, valve body) for $5500. Included this is satellite programming of the valve body (which they outsource), apparently the solenoids are timed and they have to get those programmed per what timing the kits want and that's all punched in by the programmers.
What is interesting is that Ford/GM 10-speeds are very similar in many respects (co-developed as we all know), but they have yet to fully rebuild a GM unit. The Fords, they have been consistently getting 1-2 units / week on everything from Rangers to 1/2 tons to super duty trucks. The ford 10-speeds have an issue with the sleeve in the CDF drum which drops out and causes clutch pack to burn out .... typically in the 80-100k mileage range.... surprisingly nothing on the GM.... but I put the word in about this valve body issue... many of these are still under warranty so I'm not surprised they haven't touched any.
What is interesting is that Ford/GM 10-speeds are very similar in many respects (co-developed as we all know), but they have yet to fully rebuild a GM unit. The Fords, they have been consistently getting 1-2 units / week on everything from Rangers to 1/2 tons to super duty trucks. The ford 10-speeds have an issue with the sleeve in the CDF drum which drops out and causes clutch pack to burn out .... typically in the 80-100k mileage range.... surprisingly nothing on the GM.... but I put the word in about this valve body issue... many of these are still under warranty so I'm not surprised they haven't touched any.
The valve body is not the only problem with these transmissions, I think the Fords have some similar issues as well, maybe not as high percentage, but I know there are some variations between the Ford and GM platforms.
I have read about the stove pipe and some of the clutch drums with failed welds and/or the clutch steels eating though the drum ears. I am hopeful that many of the newer 10 speeds have had some of the updated parts. BUT the bad problem for the GM transmissions are the helical cut pump drive gears, they side load and wear the center bosses then start whining. The solution is if you catch them earlier enough, you pull the trans and put the straight cut Ford pump drive gears in place, they are a direct drop in exchange as long as the gear bosses are not too worn.
After hours of research the stupid valve body are a BIG problem and this is pretty much a WHEN not IF situation. And at this point in time valve bodies are not available and even if they are, they likely have a lot of the same problems.
I skimmed my ATSG manual and there was info on the solenoids and how they have reference numbers on them and they will need to be programmed into the TCM if they are replaced. The good news is I am well aware of the solenoid differences and reference numbers and I will just need to mark each solenoid and keep track of everything when I take things apart and make sure the each solenoid goes back in the original location. Based on what I have researched, this valve body upgrade should need no programming, it effectively seals up any current internal valve body or spool valve leaks and also prevents future leaks.
Will see how things go, hopefully no surprises, but I can back out of what I did if necessary, but hoping this will not be the situation.
While I have been researching and thinking back about people I know with GM 4, 6 and 8 speeds and doing a lot of reading, it has become rather clear that valve body internal leaks and valve bore wear have been a BIG problem over the last 15-20 years. I had a buddy call me this morning on his Isuzu NPR box truck that went into Limp Mode and was having transmission problems. Initial indicators is his truck has a Vortec 6000 or 6.0ol GM engine with I believe is a 6L80 GM transmission. Initial indications are this may be a valve body problem similar to the 10 speed as long as the transmission has not suffered premature wear due to the valve body! Same story, earlier product!
To anyone following along, change your transmission fluid every 20k miles. If you are towing on a regular basis, depending on the loading, consider every 10-15k miles. If you plan on keeping the stop pan, consider putting a drain it is like this one.
Transmission Drain Kit
Stainless Transmission Drain Kit
I have read about the stove pipe and some of the clutch drums with failed welds and/or the clutch steels eating though the drum ears. I am hopeful that many of the newer 10 speeds have had some of the updated parts. BUT the bad problem for the GM transmissions are the helical cut pump drive gears, they side load and wear the center bosses then start whining. The solution is if you catch them earlier enough, you pull the trans and put the straight cut Ford pump drive gears in place, they are a direct drop in exchange as long as the gear bosses are not too worn.
After hours of research the stupid valve body are a BIG problem and this is pretty much a WHEN not IF situation. And at this point in time valve bodies are not available and even if they are, they likely have a lot of the same problems.
I skimmed my ATSG manual and there was info on the solenoids and how they have reference numbers on them and they will need to be programmed into the TCM if they are replaced. The good news is I am well aware of the solenoid differences and reference numbers and I will just need to mark each solenoid and keep track of everything when I take things apart and make sure the each solenoid goes back in the original location. Based on what I have researched, this valve body upgrade should need no programming, it effectively seals up any current internal valve body or spool valve leaks and also prevents future leaks.
Will see how things go, hopefully no surprises, but I can back out of what I did if necessary, but hoping this will not be the situation.
While I have been researching and thinking back about people I know with GM 4, 6 and 8 speeds and doing a lot of reading, it has become rather clear that valve body internal leaks and valve bore wear have been a BIG problem over the last 15-20 years. I had a buddy call me this morning on his Isuzu NPR box truck that went into Limp Mode and was having transmission problems. Initial indicators is his truck has a Vortec 6000 or 6.0ol GM engine with I believe is a 6L80 GM transmission. Initial indications are this may be a valve body problem similar to the 10 speed as long as the transmission has not suffered premature wear due to the valve body! Same story, earlier product!
To anyone following along, change your transmission fluid every 20k miles. If you are towing on a regular basis, depending on the loading, consider every 10-15k miles. If you plan on keeping the stop pan, consider putting a drain it is like this one.
Transmission Drain Kit
Stainless Transmission Drain Kit
Last edited:
StephenPT
Full Access Member
This guy is a tech at a GM dealership in Utah. He says to check the fill level at 167-176F (@4:32 mark)
@StephenPT
Pretty good video. I have a few problems with all the videos and procedures I have seen and maybe there is more to the puzzle.
A few things concern me about absolutely everything I have seen and found online either in video, on forums or in official tech documents.
Usually all automatic transmissions need to be checked with the engine running. When the engine shuts off a good bit of the fluid from the torque converter usually floods back to the trans pan and even pulling a fill plug when the vehicle is cold and not running you will have fluid running out of the fill plug.
Watching this guy work, unclear if his truck was 100% level, but even when he loosened the pan bolts hardly ANY fluid came out, so this leads me to believe the cold fill level was about even with the top of the pan flange.
Sure fluid expands when it warms up, but does the converter drain back on the 10L80/90 series like most other transmissions??
The next issue is this video did not show the how the transmission was brought up to 167-176F. I know from everything I have read/watched, they want you to brake torque the transmission in gear to allow the converter slip to warm the fluid. BUT this is dangerous if you do not understand how quickly the fluid temp can rise in the torque converter and how easily you could damage the torque converter. 10 seconds is probably the MAX time you want to brake torque then put the transmission in Neutral and idle for at least 1 minute to allow the torque converter to cool and the warm fluid to circulate. If you get impatient, damage can be inflicted on the torque converter.
The next issue is I have never seen my transmission temperature over 160F in worse case driving to date. I was cruising the highway 75+ keeping up with traffic for over 1 hours then came to a dead stop on a 80F day, the trans temp went from around 145F while cruising to 160F while sitting/crawling in traffic until the bottleneck was passed.
The other problem is 167-176F is WAY too hot to be playing around with any fluid, much less transmission fluid. Additionally the exhaust cross over is behind the bottom edge of the pan on the Suburban/Tahoe/Yukon/Esclade. Too easy to get burned and I would like to have an hour with the foolish GM transmission engineers that decided this entire process was even necessary. I have dealt with many of the German brands and the temp for setting the proper fluid level is 100F, nothing more than a warm shower. As long as an slightly above ambient temp can be chosen and reached, this is the way to do things. Transmission fluid expansion over temperature is predictable and the hot level could easily been determined in the lab.
I firmly believe MANY of these transmission videos are showing people how to overfill many of these transmissions. Looking at this video, you can see the OE trans pan does not have a standpipe, but had the flat area for one. If the pan has a standpipe then this is used for setting the fluid level, not the fill plug level and you can easily fill the transmission thru the standpipe connection. I have done it many times and it is actually very easy with a $6 fluid pump from the parts store!
Anyway, I am going to figure out the cold fluid level in my transmission buy checking/probing via the fill plug. I expect based on everything I have seen, if I remove the fill plug with the engine not running and the transmission is cold that no fluid will drain out! We will see, but in case fluid does leak out, I plan on capturing and measuring what comes out and will match the factory fill cold.
I will then follow up a few days and maybe a week later to verify the fill level. In the long run, I may drill my PPE pan and make a standpipe system for level checking once I am comfortable with the final transmission fill level.
Something tells me I will not have fluid level and dripping out the fill plug, but we shall see and I will update.
Again, this entire GM fluid fill procedure is so dangerous and stupid, the engineers did not need to make it this complicated.
Pretty good video. I have a few problems with all the videos and procedures I have seen and maybe there is more to the puzzle.
A few things concern me about absolutely everything I have seen and found online either in video, on forums or in official tech documents.
Usually all automatic transmissions need to be checked with the engine running. When the engine shuts off a good bit of the fluid from the torque converter usually floods back to the trans pan and even pulling a fill plug when the vehicle is cold and not running you will have fluid running out of the fill plug.
Watching this guy work, unclear if his truck was 100% level, but even when he loosened the pan bolts hardly ANY fluid came out, so this leads me to believe the cold fill level was about even with the top of the pan flange.
Sure fluid expands when it warms up, but does the converter drain back on the 10L80/90 series like most other transmissions??
The next issue is this video did not show the how the transmission was brought up to 167-176F. I know from everything I have read/watched, they want you to brake torque the transmission in gear to allow the converter slip to warm the fluid. BUT this is dangerous if you do not understand how quickly the fluid temp can rise in the torque converter and how easily you could damage the torque converter. 10 seconds is probably the MAX time you want to brake torque then put the transmission in Neutral and idle for at least 1 minute to allow the torque converter to cool and the warm fluid to circulate. If you get impatient, damage can be inflicted on the torque converter.
The next issue is I have never seen my transmission temperature over 160F in worse case driving to date. I was cruising the highway 75+ keeping up with traffic for over 1 hours then came to a dead stop on a 80F day, the trans temp went from around 145F while cruising to 160F while sitting/crawling in traffic until the bottleneck was passed.
The other problem is 167-176F is WAY too hot to be playing around with any fluid, much less transmission fluid. Additionally the exhaust cross over is behind the bottom edge of the pan on the Suburban/Tahoe/Yukon/Esclade. Too easy to get burned and I would like to have an hour with the foolish GM transmission engineers that decided this entire process was even necessary. I have dealt with many of the German brands and the temp for setting the proper fluid level is 100F, nothing more than a warm shower. As long as an slightly above ambient temp can be chosen and reached, this is the way to do things. Transmission fluid expansion over temperature is predictable and the hot level could easily been determined in the lab.
I firmly believe MANY of these transmission videos are showing people how to overfill many of these transmissions. Looking at this video, you can see the OE trans pan does not have a standpipe, but had the flat area for one. If the pan has a standpipe then this is used for setting the fluid level, not the fill plug level and you can easily fill the transmission thru the standpipe connection. I have done it many times and it is actually very easy with a $6 fluid pump from the parts store!
Anyway, I am going to figure out the cold fluid level in my transmission buy checking/probing via the fill plug. I expect based on everything I have seen, if I remove the fill plug with the engine not running and the transmission is cold that no fluid will drain out! We will see, but in case fluid does leak out, I plan on capturing and measuring what comes out and will match the factory fill cold.
I will then follow up a few days and maybe a week later to verify the fill level. In the long run, I may drill my PPE pan and make a standpipe system for level checking once I am comfortable with the final transmission fill level.
Something tells me I will not have fluid level and dripping out the fill plug, but we shall see and I will update.
Again, this entire GM fluid fill procedure is so dangerous and stupid, the engineers did not need to make it this complicated.
StephenPT
Full Access Member
He has an LM2 in that video. The LM2 runs the trans oil hotter than the gas engines. IIRC the thermal bypass on the diesel w/ 10L80 is set at 174F. Not sure why GM set the temp different other than that with the gas engine there will be a lot more unlocked TC situations. That can build heat in a hurry so they gave the gas engines some more head room in trans oil temp.
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