NEXTGEN Drivetrain valve body swap

[Master Chief BT]

Just completed the NEXTGEN valve body swap on 16 December. I went with the entire unit changeout at local transmission shop. Have about 100 miles on the NEXTGEN and huge difference already. Transmission temp on Banks IDash is about 10 degrees lower than stock GM valve body for the same drive to work. Still some firm shifting while the transmission control learns the new valve body. So far been very happy with the NEXTGEN. I can feel the more smooth shifting already and transmission shifting routine starting to settle in. This was a preemptive replacement for me. I wasn’t having issues but my AT4 is an August 2023 build and had the GEN 2 valve body and I wasn’t comfortable knowing that I was “on the clock” for limp mode prior to failure. NEXTGEN says allow 500-1000 miles for learning of the new valve body. Feel real good about the swap out already!

 

AT4 Forum Fav 👍

Rhino USA D Ring Shackle 41,850lb Break Strength - Grab one through Amazon!

[24Titanium3500]

Nice! How's she feeling now? I ordered the DIY kit and plan to tackle at next pan drop for fluid/filter.

 

[Master Chief BT]

So far of all the upgrades I’ve done…NextGen Valve Body….best one yet. I’m about 800 miles into the TCM relearn (500-1000 miles NextGen said) and settling right in. Firm shifts and transmission running 10 degrees cooler on work commute. I have the Banks Ram Air pan installed and huge improvement plus it looks badass! Thanks for asking!

 

[R467X]

Do you know if your shop had to do anything electronically to initiate the trans relearn or did they just tell you to drive it for a while?

 

[Master Chief BT]

The instructions that NextGen sent with the valve body says specifically to not reprogram TCM but to relearn on its own 500-1000 miles. I guess all the lines and “worm tracks” need to bleed the air from themselves at the beginning. After it smoothed out checked the fluid level and now it’s smoothing out and relearning very nicely. NextGen product and support is top tier for me.

 

[R467X]

The instructions that NextGen sent with the valve body says specifically to not reprogram TCM but to relearn on its own 500-1000 miles. I guess all the lines and “worm tracks” need to bleed the air from themselves at the beginning. After it smoothed out checked the fluid level and now it’s smoothing out and relearning very nicely. NextGen product and support is top tier for me.

Right on. I'm leaning toward getting the Suncoast valve body, don't want to do anything but unbolt the old one and install this one.

 

[Master Chief BT]

That’s what I did. I bought the entire valve body rebuilt by NextGen and dropped the original one and bolted NextGen back in. Good luck. You won’t be sorry and feels good knowing weak part is out.

 

[R467X]

That’s what I did. I bought the entire valve body rebuilt by NextGen and dropped the original one and bolted NextGen back in. Good luck. You won’t be sorry and feels good knowing weak part is out.

I had no idea they did that, last I looked it was a kit. Do you have a link for the one you got?

 

[Master Chief BT]

Allison 10L1000 Valve Bodies

There is nothing Next Gen Drivetrain™ has invested more time in than valve body technology, ranging from proprietary valves and separator plates to state of the art accumulation systems. If you're looking for the zenith of Allison 10L1000 valve body engineering, we've got you covered.

nextgendiesel.com

$2000 core credit sending yours back in. Buying the entire valve body you get lifetime warranty too

 

[R467X]

Allison 10L1000 Valve Bodies

There is nothing Next Gen Drivetrain™ has invested more time in than valve body technology, ranging from proprietary valves and separator plates to state of the art accumulation systems. If you're looking for the zenith of Allison 10L1000 valve body engineering, we've got you covered.

nextgendiesel.com

$2000 core credit sending yours back in. Buying the entire valve body you get lifetime warranty too

Perfect thanks

 

[R467X]

Hey I just got done removing my valve body. Nextgen no longer does the core deal due to supply issues so my truck is down for what I'm estimating 2-3 weeks.

I wanted to ask you - what refill procedure did you follow? Did you also power break your truck until your temp or did you just go on a drive?

Edit: disregard. I missed the transmission shop part. But how is everything holding up so far? I'm going to do trans tuning after this

 

[Master Chief BT]

Hey I just got done removing my valve body. Nextgen no longer does the core deal due to supply issues so my truck is down for what I'm estimating 2-3 weeks.

I wanted to ask you - what refill procedure did you follow? Did you also power break your truck until your temp or did you just go on a drive?

Edit: disregard. I missed the transmission shop part. But how is everything holding up so far? I'm going to do trans tuning after this

Holding up outstanding. I’ve got about 8,000 miles on my NextGen valve body and about 2,000 of that towing. I’ve noticed my tranny temps are running cooler and shifting is smooth. For me it’s been a quality product. I like the fact that it shifts strong and temps drop with my Banks Ram Air tranny pan when driving open air in front towing. Best truck money I’ve spent so far.

 

[R467X]

Holding up outstanding. I’ve got about 8,000 miles on my NextGen valve body and about 2,000 of that towing. I’ve noticed my tranny temps are running cooler and shifting is smooth. For me it’s been a quality product. I like the fact that it shifts strong and temps drop with my Banks Ram Air tranny pan when driving open air in front towing. Best truck money I’ve spent so far.

I appreciate the response..What do your temps run at empty? I

 

[Master Chief BT]

I appreciate the response..What do your temps run at empty? I

Temps all based on ambient right…so normally a 90 degree Texas day with a 15 mile commute each way, stop n go traffic I will see about 130 degrees max trans temp….towing Airstream at highway speed same day I’ll see about 136-140 degrees. I do notice more aggressive shifting meaning a little higher engine revs before shifting up. I also think that is NextGen goal on their valve body. Relearn period for me took about 3,000 miles to get settled in for both tow/haul mode and regular drive mode. Good luck with your rebuild

 

[R467X]

Temps all based on ambient right…so normally a 90 degree Texas day with a 15 mile commute each way, stop n go traffic I will see about 130 degrees max trans temp….towing Airstream at highway speed same day I’ll see about 136-140 degrees. I do notice more aggressive shifting meaning a little higher engine revs before shifting up. I also think that is NextGen goal on their valve body. Relearn period for me took about 3,000 miles to get settled in for both tow/haul mode and regular drive mode. Good luck with your rebuild

Right on. I was getting 144 roughly on all stock setup, no towing. But I'm in the communist $#IT hole of the PNW so it hardly gets too warm around here.

I'm also doing the banks pan - will see what kind of temps I get.

Was actually one of the easiest jobs I've ever done and I don't mess with trannies. For anyone reading this thinking about diy - it's very easy.

I drilled into the lowest part of the trans pan and flushed all the fluid out. From then on it's easy sailing and the only bolts you take off the VB are the ones with an arrow pointing at them.