We’re it me, I’d go with the full VB from next gen to give me the warm and fuzzies. Or Suncoast, but I’ve not really looked at them. A large amount for a single part, but way cheaper than a new truck as you mentioned, and all indications are that it’ll solve this issue.

It would be nice if anyone here had info on what they paid for an install or what the results were following the install. Maybe on the FB groups there’s some feedback, but I don’t do FB.

Then there’s finding a transmission shop that can be trusted. Maybe a well established performance diesel shop?

 

I already have a trusted mechanic in my hometown to do it, an independent GM only guy with 40 years of experience. He is the only guy i would trust to do this other than myself ( again i have no place to work on it). Years ago i had him harden the 4l60 in my 96 1500 some upgraded parts( those were notorious for sun gears back then) and never had another issue with it in over 200k miles of towing a boat.

 

If it were me, I would at least check into trading. The market is all over the place, and you might do better than you think. You could also think they are nuts with the offer. All makes have their issues, but I had had enough of GM and their reluctance of good customer service. I'd had multiple cracked sliding window frames, a rough ride no one could figure out, and seats that were less comfortable than middle school bleachers. Mechanically, I had no issues, but never ran one out of warranty, either. I think that GM's EV push sacrificed their reliability and dependability of their real money makers, the trucks and SUVs. Even the once heralded gas V8s are touch and go now. Pick your poison with brands, I suppose, and hope for the best.

GM is not off my list by any means, but I'd like to see substantial changes in design, reliability, and leadership.

 

So i have. Dealerships and Texas, Arizona and Colorado that i have been thru in the last 3 months all are well aware of the issues with these trucks and all gave me what i think are lowball offers well below where i would want to be trading it in. The best offer i got as $45k which is horrible for a $94k truck thats only one model year old. One Ford dealer in Colorado told me flat out he would not even take it in trade knowing the transmission issues as soon as i mentioned trading in my GMC.

 

Adding to this-
Next generation youtube videos suggested that prior to failure line pressure may be reduced and clutch pack would suffer. Someone can correct me on this or add to it. I myself am contemplating the nextgen 800ish kit. I have no failure or indications but it may mack sense to just bypass possible damage slowly creeping in due to line pressure before s code or failure.

Anyone done the kit at a shop and or what should I expect to pay in labor?

Boxer, you may want to check fluid condition. Might be better to get to this before a failure.

 

I should check the fluid. Just have to read up on how to do it, since they felt a dipstick was unnecessary.

On a side note I just looked at my local Ram dealer. A 2500 Ram 2500. 99k. wtf. Literally muttered that to myself when it popped up. Wow. Didn’t even bother looking at the 3500 SRW/DRW. So, again, under 5k I’m guessing for a valve body and install isn’t so bad. lol.

 

Do it running or you may lose a bit more and have to add. Nothing should come out until you reach the correct temperature. If it has been awhile it might just be best to go ahead and drop the pan so you can get an idea of what may be in there. As you said the performance of has changed gradually, a fluid refresh may help until you can get a plan together.

10L1000 Servicing

Here is what I have received from a friend who is a long time gm tech. Make sure you only use the ULV fluid. Roughly 14.4 qts.

www.duramaxforum.com

https://www.duramaxforum.com/threads/10-speed-transmission-service.1028300/

 

I just installed the NextGen DIY kit with the new shift valves last weekend. I have only put 80 miles on the truck since the install but it seems to be greatly improved. I was getting a shutter anywhere from 5-10th gear under light throttle. The parts that come in the NextGen kit look to be very high quality. It took just over 16 quarts of ULV to fill the transmission. It took about 8 hours for me to complete the kit.

 

This is great info, thanks.

Can you tell me more about the shift valves? Are those optional?

 

Looks like it comes with the shift valves, but uses your OEM solenoids.

I looked at Suncoast and they’re substantially cheaper for a whole new pump and VB. More than the VB upgrade kit from NG, but way less then than the whole VB from NG. Don’t know if one is really better than the other.

 

And that's another thing im trying to figure out. Right now suncoast has a 20-30 day build time due to "increased demand" and it looks like the price has gone up to, they were 1500 now its 2k. I would think someone could comment on having one in their truck but i have read no info on it anywhere.

From what i see in this video its a factory valve body with what equates to a shift kit. I have the latest valve body in my truck already and while i have not heard of any failures on it yet as i mentioned mine feels like its acting differently than post repair and more like it did prior to it failing which is why im concerned.

 

So what is the difference of the two? VB to VB, is there anything major that separates them from one another? I'm on here wondering this, I had my updates at the dealer. I have just over 32k and the truck is doing fine. I have a 12k gooseneck trailer that for the last two years has been towing fine, I would rather not get stuck on the road with it. I think the cost to do the fix is small price to eat compared waiting for GM with no truck. Oh and have to pay to get the trailer home would be way more than the fix cost if I did it myself; or a shop to do it. I now have the issue of do it myself or find a shop that I trust to do it????

So is there anyone here from the Hampton Roads area in Virginia? Shoot me a pm if you have good/bad info on sops in the area

 

Thanks for the feedback. Did you do the work yourself or have a shop do it? How many miles on the truck?

I really like my truck so more and more it seems worth the expense to either get the whole VB or at least the kit from NG.

 

Boxer1200,
I did the work myself. I do have a vehicle lift so I wasn't laying on the floor but it could be done that way also. It might be easier laying on the floor since the valve body is hard to hold in place while you pull / put a couple of bolts in it. I recommend having a second set of hands to hold it while you pull the last couple of bolts out and to re-install it. The truck is a 22 DRW with 23000 miles. Took me around 8 hours from start to finish. I took a lot of pictures so everything went back together just like it came out.

 

all this infromation is why my 2002 LB7 keeps going up in value... 244000 and not even a service engine light. that includes injectors.......... knock on wood..

 

Lets hope you get many more trouble free miles.


Talked to Next Gen today and im ordering the upgrade kit with the shift valves. I think that will get me where i need to be. We did talk about hos it was driving and the bucking/surging when im towing. The guy i talked to thinks i'm on my way to another failure so im going to have the parts shipped to my shop so they will be there when im home in a couple weeks.

 

Here's my NextGen 10L1000 "Allison" tranny valve body upgrade install story for anyone who needs something to put themselves to sleep.....

Let me start by saying that I do feel a little butt hurt about finding out my "I can finally afford to buy the truck I've always wanted" didn't really have an Allison tranny installed after all! WTF?? Had I known that little gem of information prior to purchase, I know I wouldn't have pulled the trigger on it. I feel dup'd and that's a yucky feeling I haven't ever had about GMC, let alone it being my new problem. Like many of you, I'm in the position of trading in (not in my cards right now) or making horse crap taste like ice cream.....well shit.....I'm staring fiber laced ice cream right in the face.....chocolate chip mint perhaps!?.....ok, I probably took that too far!...... After working through the five stages of Grief, funny tasting ice cream it is....but oh man....that aftertaste is BAD!

The road to understanding took me to the Forums (this one included) and eventually I decided that before my tranny really took a dump while towing out to the Black Hills in Sept, that I was going to go down the "peace of mind" avenue. I tend to be a bit proactive anyway, so settled on the Next Gen Carbon Valve Body Upgrade Kit. I ordered the kit and also an upgraded tranny pan from PPE. Flash forward to doing it myself....

With the truck up on jack stands, I was able to follow the removal instructions fairly easily. Even though I consider myself a "58 year old, been working on my own vehicles my whole life and know which end of a ratchet to hold" kind of guy, I still found a way to screw up changing the new upgraded valves into the valve body. And I was meticulous no less! Installed it in the truck....NO JOY! A local diesel mechanic recommended NoZone Diesel to talk to and I ended up shipping the valve body off to them for proper assembly. In hind sight, this ended up being a blessing in disguise as my valve body was not bored well from the factory (common problem apparently) and they ended up re-boring during the reassembly process. Re-installed and is now working well.....BUT, there are a few take-aways for you to consider if you're thinking about this upgrade.....

1. Just have a reputable tranny guy do the valve insert/rebuild. It is very complicated in there and the instructions from NextGen just weren't detailed enough. If you have some experience with auto trannys, then ok if you can be detailed enough, otherwise have that part done by a pro. No Zone Diesel did me good, but if you're not in Ohio, you're shipping like I had too. As directed by them, to protect the valve body, I shipped it wrapped up like fine crystal....then placed it into the PPE pan....then into a box with enough bubble wrap and padding to cushion an old sweaty stick of dynomite. The removal, replacement and pan install went just fine for a wanna-be do it myself guy.
2. When installing the valve body into the tranny, make sure you get the shift lever into the correct slot on the valve. If you don't know what I'm referring to here, contact me here and I'll do what I can to walk you through it.
3. After you've gone through GM's tranny fill procedure, the fluid level will probably still be off. After a few hundred miles, it started to shift odd. After a consult call with NextGen, I went through the fill procedure again and figured out I was 1+ Qt's low. That tranny must be nice and warm and all gears manually run through before final check. Take the time and do it right Gomer!
4. Last one and here's the biggy. When towing at hwy speeds for a few hours, the truck started shifting hard....really hard!....and I started to see my tranny temps jumping up well over 200. Note that I was towing in Automatic (D)rive with Tow Mode turned on. After trying to sort it in my head, I said to myself, "it almost feels like it's hanging up in 10th gear". I shifted to manual and set my upper limit gear at 9. Problem solved! No more hard shifting and the tranny temps immediately dropped down to the 160's.

I hope this write up helps you if you're considering this move and feel free to post to any questions and I'll do my best to answer....just remember that my advice is only worth what you're paying for it.....in other words, chocolate chip ice cream.

B

 

Here's my NextGen 10L1000 "Allison" tranny valve body upgrade install story for anyone who needs something to put themselves to sleep.....

Let me start by saying that I do feel a little butt hurt about finding out my "I can finally afford to buy the truck I've always wanted" didn't really have an Allison tranny installed after all! WTF?? Had I known that little gem of information prior to purchase, I know I wouldn't have pulled the trigger on it. I feel dup'd and that's a yucky feeling I haven't ever had about GMC, let alone it being my new problem. Like many of you, I'm in the position of trading in (not in my cards right now) or making horse crap taste like ice cream.....well shit.....I'm staring fiber laced ice cream right in the face.....chocolate chip mint perhaps!?.....ok, I probably took that too far!...... After working through the five stages of Grief, funny tasting ice cream it is....but oh man....that aftertaste is BAD!

The road to understanding took me to the Forums (this one included) and eventually I decided that before my tranny really took a dump while towing out to the Black Hills in Sept, that I was going to go down the "peace of mind" avenue. I tend to be a bit proactive anyway, so settled on the Next Gen Carbon Valve Body Upgrade Kit. I ordered the kit and also an upgraded tranny pan from PPE. Flash forward to doing it myself....

With the truck up on jack stands, I was able to follow the removal instructions fairly easily. Even though I consider myself a "58 year old, been working on my own vehicles my whole life and know which end of a ratchet to hold" kind of guy, I still found a way to screw up changing the new upgraded valves into the valve body. And I was meticulous no less! Installed it in the truck....NO JOY! A local diesel mechanic recommended NoZone Diesel to talk to and I ended up shipping the valve body off to them for proper assembly. In hind sight, this ended up being a blessing in disguise as my valve body was not bored well from the factory (common problem apparently) and they ended up re-boring during the reassembly process. Re-installed and is now working well.....BUT, there are a few take-aways for you to consider if you're thinking about this upgrade.....

1. Just have a reputable tranny guy do the valve insert/rebuild. It is very complicated in there and the instructions from NextGen just weren't detailed enough. If you have some experience with auto trannys, then ok if you can be detailed enough, otherwise have that part done by a pro. No Zone Diesel did me good, but if you're not in Ohio, you're shipping like I had too. As directed by them, to protect the valve body, I shipped it wrapped up like fine crystal....then placed it into the PPE pan....then into a box with enough bubble wrap and padding to cushion an old sweaty stick of dynomite. The removal, replacement and pan install went just fine for a wanna-be do it myself guy.
2. When installing the valve body into the tranny, make sure you get the shift lever into the correct slot on the valve. If you don't know what I'm referring to here, contact me here and I'll do what I can to walk you through it.
3. After you've gone through GM's tranny fill procedure, the fluid level will probably still be off. After a few hundred miles, it started to shift odd. After a consult call with NextGen, I went through the fill procedure again and figured out I was 1+ Qt's low. That tranny must be nice and warm and all gears manually run through before final check. Take the time and do it right Gomer!
4. Last one and here's the biggy. When towing at hwy speeds for a few hours, the truck started shifting hard....really hard!....and I started to see my tranny temps jumping up well over 200. Note that I was towing in Automatic (D)rive with Tow Mode turned on. After trying to sort it in my head, I said to myself, "it almost feels like it's hanging up in 10th gear". I shifted to manual and set my upper limit gear at 9. Problem solved! No more hard shifting and the tranny temps immediately dropped down to the 160's.

I hope this write up helps you if you're considering this move and feel free to post to any questions and I'll do my best to answer....just remember that my advice is only worth what you're paying for it.....in other words, chocolate chip ice cream.

B

Thanks for the writeup. Enjoy the black hills. If you do end up needing any kind of dealer support while you are out there Granite Buick GMC in Rapid City is good. I had them do some front end work while i was in the Badlands NP with my RV. I had a bad pitman arm and they also found another loose component that the dealer i brought it to in Denver missed....

I detailed some of my install story on another thread but i figure i should update here since i started this thread. So i took my truck to my mechanic to have the kit installed last Tues. Its still not done yet. So he did the original install and when we drove the truck it was shifting really hard from 2-5th gears. 5-6 and up to 10 were nice and smooth and quick. He checked the fluid level and it was not low. After a troubleshooting call it was suggested to try a fast relearn on the TCM. That's where it all went badly, like really badly. The truck started doing the relearn and the scan tool said it was complete. After that it would not shift into drive or reverse. The scan tool showed it as being in gear but the truck would not move. We called Nextgen again and they originally suggested fluid level but that was not it. After talking with them as well as a GM dealer shop he is friends with they think something happened to the TCM and it needed to be reflashed. He got the remote reflash tool from his buddy and made an appointment with GM to do the remote reflash. That failed, it would not load the software, still had to pay for it too. From there we had it hauled to his buddies dealer where he was able to reflash the TCM with his GM MDI tool. It now tries to shift the gear but i still dont have reverse, forward is fine but still shifting hard. At this point Nextgen thinks its a stuck valve(s) and i probably have a bore or two that are out of tolerence or out of round which apperently is common and is what is causing the sticking. The only recourse is to pull the valve body again. This time its being sent to Nextgen to have them work thier magic on it and get me back on the road. Hopefully the VB will be pulled tomorrow after it gets hauled back to my mechanic and we can get it sent off to nextgen and fixed.

This whole deal has been a freaking nightmare and my personal suggestion to anyone looking to do this, pony up and get the full valve body. There are too many variables in the factory one and when they rebuild them with thier parts they are taking the time to machine them so the valves will fit properly.

 

Sorry to hear you guys are having issues getting your valve body rebuilt. Hopefully everything gets worked out soon. I see Sonnax is now offering replacement valve kits for the 10L1000. I’m not sure if I could help you out but I am in NW Wyoming.

 

I had the nextgen kit installed and still have a weird sometimes it does sometimes it don't, abrupt hard down shift from 5 to 4. Not always and so far is not trans temp dependent, feels more like it is based on the programming getting hung up trying to down shift through the gears and slamming to 4th before going down to 3rd if I am coming to a faster stop. If I let it coast with engine brake on it usually shifts down fine. I had the relearn done and doesn't really seem to have helped much.

I felt the same as Bobby did, finally get it and hey I got bamboozled. I think I will give the fluid level check procedure a try see if its a bit low, can't hurt at this point.

 

Thought i would post a quick update since its been a minute.... Still don't have my truck back. My valve body has been sent to Nextgen and i just got thew shipping notice that its on its way back now. No report form them on what they found wrong. I have asked but crickets on an answer. Hopefully i will have my truck back early next week.

 

So another quick update for anyone interested. Got the valve body back from next GEN. It’s been installed and now I have a solenoid D sticking error code every time it shifts from 4th to 5th and it goes in the limp mode. This is not going well. I regret starting this entire process, a simple upgrade has turned into a complete nightmare. My truck has been down now for three weeks, trying to get this all resolved with no end in sight.

Not only do I have now almost $4000 invested into A. valve body. I have probably four days worth of mechanic time trying to troubleshoot this whole thing uninstalling and reinstalling parts about 45 quarts of fluid and now I have other expenses upstream because I’ve had to cance cancel, nonrefundable stays, etc. while we’re stuck again with our RV. This was supposed to be a simple three hour install.

 

This was posted on DuramaxDiesels regarding sticking.

"Finally got to talk to the owner or whoever at next gen. He's extremely knowledgeable and knew immediately the 2 possible causes of my symptoms. It ended up being sticky shift valves. His latest kit doesn't give you the option to opt out of these shift valves like the last kit I did. They are billet steel valves that replace the OE aluminum. I basically needed to "hone" the bores, using the valves themselves. Or worst case, a round brush.
Anyways, I cycled all 6 valves a whole bunch and then reassembled the VB. It's doing great now. There really wasn't anything I noticed as far as them sticking but what he said made sense. "

 

I hope I can get further along without these issues. ‘24 3500 Ultimate DRW and 38’ GN tri-axle cargo (GVW 26K). Came from a Ram 3500 MegaDually CTD Aisin.
GMC gears 8,9&10 are overdrive. Standard axle ratio is 3:42.
My Ram had (I ordered the 3:73’s for a compromise between economy and max tow). Only 6 gears in the Aisin. 38’ GN Tri-axle cargo trailer. I would lock out 6th when I hooked up. If it got steep, locked out 5th. In tow haul the whole time. Haven’t hooked up the trailer with my new Sierra 3500 DRW yet. I was at 30,740# combined weight from CT to CA to AK with the Ram. Thats a little bit of mountain along that path. With the GMC, I would probably start with locking out 9&10 to start. Seems that heavy towing heavy with those high gears and running up in overdrive territory is gonna put some strain on the transmission. Doubt that I’ll ever pull that much again. Just my $0.02.

 

I hope I can get further along without these issues. ‘24 3500 Ultimate DRW and 38’ GN tri-axle cargo (GVW 26K). Came from a Ram 3500 MegaDually CTD Aisin.
GMC gears 8,9&10 are overdrive. Standard axle ratio is 3:42.
My Ram had (I ordered the 3:73’s for a compromise between economy and max tow). Only 6 gears in the Aisin. 38’ GN Tri-axle cargo trailer. I would lock out 6th when I hooked up. If it got steep, locked out 5th. In tow haul the whole time. Haven’t hooked up the trailer with my new Sierra 3500 DRW yet. I was at 30,740# combined weight from CT to CA to AK with the Ram. Thats a little bit of mountain along that path. With the GMC, I would probably start with locking out 9&10 to start. Seems that heavy towing heavy with those high gears and running up in overdrive territory is gonna put some strain on the transmission. Doubt that I’ll ever pull that much again. Just my $0.02.

I would lock out 8th too if you are worried about overdrive. I will say that doing that is not going to help the valve body life, it sure has not for me, I always tow my trailer in 7th max speed 60mph and it still ate the vb.....

 

So another update on my situation. I finally got my truck back today and all seems good. The Valve body had to go back to Nex Gen a second time but i blame UPS for that. The D solenoid which is on the outside was slightly moved out of position and that was what was causing the code and bad shift. They sent me an overnight label, fixed it, retested everything and sent it back to my shop overnight. It got installed today and i was able to drive it home.

My first impressions are really good. Its still learning the new setup but shifts are great, quick and under light throttle almost imperceptible. It kind of reminds me of how my old RAM with the 8 speed ZF shifted. Temps are also lower than it was prior. Running down the highway in 70 deg ambient the trans mission was running 120 where it used to run 145 almost all the time. I'm sure its a combo of the kit removing the thermostat and the Banks pan i also put on at the same time. Towing test will be a week from today, its its anything like the first drive today was i think ill be a happy camper.

 

I've heard enough. Next gen are a bunch of hacks. You don't use orings on valves in an attempt to fix crappy machining or wear issues on a used VB due to the fact orings cause the sticking issues above and over time long term wear on a rubber oring or worse break and send bits of rubber into VB. You also don't remove the thermostat. Fluid needs to be a certain temp so that the computer can anticipate clutch engagement characteristics. Also cold fluid does not get rid of the water. Wait until it's 30below and running without a tstat in trans might throw codes. IDK but cold fluid is generally as bad as hot fluid.

In aircraft engines it's a cardinal sin to have oil too cold, and on lycomings they have guess what A THERMOSTAT.

Good luck guys, hope that kit eventually works out. What a nightmare.

 

I've heard enough. Next gen are a bunch of hacks. You don't use orings on valves in an attempt to fix crappy machining or wear issues on a used VB due to the fact orings cause the sticking issues above and over time long term wear on a rubber oring or worse break and send bits of rubber into VB.

And yet you see companies like Sonnax that have done the same thing, are they hacks too? Here is a link to one of their upgrades for a ZF transmission and guess what they use O-rings for..

Zip Kit® - ZF8-ZIP

Sonnax Zip Kit ZF8-ZIP targets the root cause of multiple complaints by sealing the critical circuit pressure losses in ZF8HP45/55/70 and Chrysler 845RE

www.sonnax.com

 

As far as I can tell those orings are on static end plugs and caps not on moving valves and yes in static applications are just fine.

The valves in PWM solenoid controlled trans mission "buzz". Moving far move times than just during a shift.

If orings worked then the OEM would have used them along time ago as they are far cheaper than trying to machine a valve/bore to within .0002".

Go find a real trans shop and ask them.

 

As far as I can tell those orings are on static end plugs and caps not on moving valves and yes in static applications are just fine.

The valves in PWM solenoid controlled trans mission "buzz". Moving far move times than just during a shift.

If orings worked then the OEM would have used them along time ago as they are far cheaper than trying to machine a valve/bore to within .0002".

Go find a real trans shop and ask them.

Read a little closer.....

Direct from the contents list
"Solenoid O-Rings (24) Various Sizes"


O-rings have been used on moving parts in hydraulics for ages, under significantly more pressure too. If they are of the right material and durometer id bet they will work just fine.

 

What was your decision since I see this post was created in May? I had someone do the next gen rebuild kit on a brand new transmission after the valve body in the original transmission failed and trashed the transmission. I too went back and forth and I also had no where to work on it myself. I found a diesel shop within 20 minutes of my home that specifically works on allison transmissions and they installed the next gen kit at a reasonable price.

 

I thought i detailed it in the thread but ill give you the cliff notes.

Got the Next Gen kit and had it installed by a mechanic that i trust that has been working on transmissions for over 30 years. He installed the kit and i had really poor shifting and no codes, he pulled the VB again to make sure all the valves were free per Next Gen tech support. , we talked to Next gen and they suggested he try a fast relearn using his Snapon scan tool. That was performed and "successful" according to the tool and things went haywire, lost all gears. TCM needed a reflash and i ended up sending the valve body to Nextgen to have them rebuild it and machine the bores to fit the new valves. Got it back and UPS damaged it and bent the D Solenoid, back to nextgen it went and they fixed it again. Its back in the truck and seems fine now.