2021 2500 6.4 new issue

[Dgman]

Hello, I'm not sure if this is the right place to post but here goes. 2021 2500hd 6.4 I have just over 30,000 miles on the clock. I live in NJ which is mostly flat land. This week I'm down in Tennessee. I'm noticing a kind of bucking, surging ,hesitation issue. It's hard to explain. Happens under light acceleration from.. say a stop light or on an incline at low speed. With normal pressure on the pedal...ie not mashing it to take off in hurry. It happens in normal drive mode, in tow/haul mode, and manual shift. It's even more noticeable with my travel trailer behind me. No engine lights on. The last tank of fuel i ran 93 octane and no difference. Any ideas? Thanks

 

[Dgman]

I guess should say the truck is stock except a flowmaster exhaust system. Which by the way i regret. The drone is horrendous. Especially pulling my camper. Most likely going back to stock after this trip

 

[Poolmonkey]

I guess should say the truck is stock except a flowmaster exhaust system. Which by the way i regret. The drone is horrendous. Especially pulling my camper. Most likely going back to stock after this trip

Mine did something like that for a bit, usually upon start up and when easing around in parking lots..where I noticed it most. It seems to have stopped.
Almost seemed like the trans was thinking of shifting but wasn’t sure whether to or not.

 

[Dgman]

Mine did something like that for a bit, usually upon start up and when easing around in parking lots..where I noticed it most. It seems to have stopped.
Almost seemed like the trans was thinking of shifting but wasn’t sure whether to or not.

It stopped on its own?

 

[Poolmonkey]

It stopped on its own?

It did..hasn’t done it in quite a while. Not saying the two issues are the same, just that your describing of symptom matches precisely. I never tried manual shift mode during the episodes.
The truck would surge, hesitate, surge, hesitate…bucking a bit while all of that under light throttle, the kind of throttle one would use navigating a parking lot.
Have you done anything lately that would cause the trans to ”relearn”….had battery disconnected or such?

 

[Dgman]

It did..hasn’t done it in quite a while. Not saying the two issues are the same, just that your describing of symptom matches precisely. I never tried manual shift mode during the episodes.
The truck would surge, hesitate, surge, hesitate…bucking a bit while all of that under light throttle, the kind of throttle one would use navigating a parking lot.
Have you done anything lately that would cause the trans to ”relearn”….had battery disconnected or such?

No. The only thing different is the terrain. Nj is flat. I've been running mountain roads for almost 2 weeks now

 

[Rockcrawlindude]

I noticed that on two separate occasions when my wife was driving my truck and i was riding shotgun after I had a few drinks. Both times it was at a slow speed and it bucked/surged a handful of times. It was like being in one too high a gear and letting out the clutch.

I chalked it up the truck/trans mapping being accustomed to my driving and she was probably lighter on the fuel and it upshifted funny or something. I’m not 100% sure if that’s what happened but I’ve not experienced it from the driver seat.

I also have 30k miles over the last 4 years ownership.

 

[Dgman]

So it's possible my truck is trying to relearn because of the different terrain?

 

[jetrinka]

Perhaps. Give it some time and see.

If you want to help the process along you might as well grab a throttle body gasket and pull the throttle body off for a good cleaning. There isn't any special relearn process. I removed mine and cleaned it at 30k and it was dirty. Not horrible by any means but needed it. I wasn't experiencing anything weird and didn't notice a difference with anything - was more for maintenance.

 

[kevin588127]

Mine does something similar under light acceleration. Almost like the trans doesn't know what gear it wants to be in or something with the torque converter. Only does it in 3rd gear or so and under very light acceleration. I'd heard from a member on here that they were working on update for this issue. Haven't heard if they got it done or if it cured this particular issue.

 

[sstoner911]

Air Filter Stock and clean?

 

[Hunter11]

Mine just started doing this about a week ago. Feels like a bucking/surging under light throttle. I have 8500 miles on the truck and run it on Valero or Shell 89 octane.

 

[BadKarma]

I’ve had this in my 1500 and was told it was normal. About 1000 miles later the dealer came and picked the truck up and had to re-flash the TCM because it was “due for an update”

 

[matemike]

I've had my 2022 2500 Hemi with 8spd for one year now. Little over 15,000 miles. It has had this hesitating, shifty, jumpy, jerky transmission issue since day one. I figured it was learning my driving style. Well it seems to be getting worse; it happens more often, but it's the same "level" of jerkiness is how I should say it.

I towed our 8k pound camper a few times and it did it then as well, but I was usally harder on the pedal to get going so the upshifting was okay. The downshifting sometimes is very annoying. From 5th gear, you can feel it stutter to 4, 3, 2 all during the last 30 ft of coming to a stop at a red light. During light acceleration you can feel the trans jump and hesitate all over the middle gears, especially right after a cold start up. Again, i'm stressing light acceleration.

I absolutely LOATHE letting a dealer touch my truck. I have discovered and fixed more things on my truck myself than the entire crew at my local dealer could dream of doing. I want to take it to a trusted mechanic and let him flush the trans and add new fluid. But if anyone here has heard of Ram coming out wirh an ECM flash for the wondering 8spd transmission issue, I'm all ears. I might even let my dealer flash it for a legit recall. Sad to say, but this big beautiful truck is almost annoying to drive now. It's a new truck, so I love how quiet it is compared to my old truck. I love the radio and all the features it has. But I think MOPAR screwed smoething up when mating this 6.4L Hemi to the 8spd transmission and 3.73 gears.

 

[Rockcrawlindude]

I've had my 2022 2500 Hemi with 8spd for one year now. Little over 15,000 miles. It has had this hesitating, shifty, jumpy, jerky transmission issue since day one. I figured it was learning my driving style. Well it seems to be getting worse; it happens more often, but it's the same "level" of jerkiness is how I should say it.

I towed our 8k pound camper a few times and it did it then as well, but I was usally harder on the pedal to get going so the upshifting was okay. The downshifting sometimes is very annoying. From 5th gear, you can feel it stutter to 4, 3, 2 all during the last 30 ft of coming to a stop at a red light. During light acceleration you can feel the trans jump and hesitate all over the middle gears, especially right after a cold start up. Again, i'm stressing light acceleration.

I absolutely LOATHE letting a dealer touch my truck. I have discovered and fixed more things on my truck myself than the entire crew at my local dealer could dream of doing. I want to take it to a trusted mechanic and let him flush the trans and add new fluid. But if anyone here has heard of Ram coming out wirh an ECM flash for the wondering 8spd transmission issue, I'm all ears. I might even let my dealer flash it for a legit recall. Sad to say, but this big beautiful truck is almost annoying to drive now. It's a new truck, so I love how quiet it is compared to my old truck. I love the radio and all the features it has. But I think MOPAR screwed smoething up when mating this 6.4L Hemi to the 8spd transmission and 3.73 gears.

Sorry you’re having problems with yours. Hope they get it sorted out. I think there is something wrong with yours. Do multiple people drive it by chance?

It’s not the platform itself. The zf 8 speed is undisputed best in class. Easily best torque converter transmission on the planet. But, any manufacturer can send a lemon out the door.

I have 3.73s as well and the trans is smooth as glass with a load on it. It can be clunky at times at slow speeds, or coasting downshifting unloaded etc. but 99% of the time it’s glassy smooth

 

[jetrinka]

I've had my 2022 2500 Hemi with 8spd for one year now. Little over 15,000 miles. It has had this hesitating, shifty, jumpy, jerky transmission issue since day one. I figured it was learning my driving style. Well it seems to be getting worse; it happens more often, but it's the same "level" of jerkiness is how I should say it.

I towed our 8k pound camper a few times and it did it then as well, but I was usally harder on the pedal to get going so the upshifting was okay. The downshifting sometimes is very annoying. From 5th gear, you can feel it stutter to 4, 3, 2 all during the last 30 ft of coming to a stop at a red light. During light acceleration you can feel the trans jump and hesitate all over the middle gears, especially right after a cold start up. Again, i'm stressing light acceleration.

I absolutely LOATHE letting a dealer touch my truck. I have discovered and fixed more things on my truck myself than the entire crew at my local dealer could dream of doing. I want to take it to a trusted mechanic and let him flush the trans and add new fluid. But if anyone here has heard of Ram coming out wirh an ECM flash for the wondering 8spd transmission issue, I'm all ears. I might even let my dealer flash it for a legit recall. Sad to say, but this big beautiful truck is almost annoying to drive now. It's a new truck, so I love how quiet it is compared to my old truck. I love the radio and all the features it has. But I think MOPAR screwed smoething up when mating this 6.4L Hemi to the 8spd transmission and 3.73 gears.

Yeah I agree with @Rockcrawlindude sorry you're having issues but it sounds like a lemon cause the ZF is typically an awesome transmission. Mine has 34k on it now with zero problems - I always thought it was one of the best transmissions I've had in a vehicle.

 

[Rockcrawlindude]

Sorry you’re having problems with yours. Hope they get it sorted out. I think there is something wrong with yours. Do multiple people drive it by chance?

It’s not the platform itself. The zf 8 speed is undisputed best in class. Easily best torque converter transmission on the planet. But, any manufacturer can send a lemon out the door.

I have 3.73s as well and the trans is smooth as glass with a load on it. It can be clunky at times at slow speeds, or coasting downshifting unloaded etc. but 99% of the time it’s glassy smooth

I ask if multiple people drive it because when my wife drives it and I’m riding (one too many margs) it will do weird clunky downshifts more often, especially in our neighborhood

Someone with more knowledge of the programming can explain how the transmission learns driving styles but that’s my experience/thoughts.

 

[matemike]

My wife drives it very very rarely. Behaves the same when I ride shotgun, I feel.
When she drives solo she never mentions anything, but when I ask, she says it could definitely be smoother. She did say once when I was driving, we were pulling the camper, "dang, think thing clunks down hard when coming to a stop, huh?" And it happened the next day when not towing and she said "does it always do that?" Truck had less than 5k miles on it at the time.

A co-worker drove it when it was brand new and he didn't say anything.

It's a toss up whether I get my local shop to flush trans, look for metal, and add new fluid, or take it straight to the dealer and get it looked at...?

Sorry for jacking this thread. It was either this or start a new one

 

[Rockcrawlindude]

My wife drives it very very rarely. Behaves the same when I ride shotgun, I feel.
When she drives solo she never mentions anything, but when I ask, she says it could definitely be smoother. She did say once when I was driving, we were pulling the camper, "dang, think thing clunks down hard when coming to a stop, huh?" And it happened the next day when not towing and she said "does it always do that?" Truck had less than 5k miles on it at the time.

A co-worker drove it when it was brand new and he didn't say anything.

It's a toss up whether I get my local shop to flush trans, look for metal, and add new fluid, or take it straight to the dealer and get it looked at...?

Sorry for jacking this thread. It was either this or start a new one

No worries hope you get it figured out.

 

[Express sn95]

I experience something similar in my 22 Ram 2500 which feels almost like it's slipping. It also clunks on half of the downshifts coming to a stop. I am hoping that there is or will be an update for the transmission when I take it in for service.

Check out this thread to see others complaints.

Adaptive Transmission has power issues when shifting

Hey gang. I have had my 2022 2500 6.4 hemi for about six months and I continue to have hesitations/small jerking issues when shifting. It usually happens in third or fourth gear. Is that the adaptive transmission trying to learn what gear I should be in or do I have a serious issue? Only 4K...

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