2015 ram 3500 jerking hard

It is NOT a problem. You are at that moment where it drops into 1st that in reality is like having a granny low then immediately it hits 2nd so it causes a jerking motion the harder you are pushing the go pedal the more noticeable it is. It's not slipping and the engine is not falling out.

These Aisin's act a lot like a "built" trans, that is a good thing.

Mine does the same thing if I start off then let up a bit in traffic.

steadypraying426 wrote:
Please forgive my ignorance but what is a re-flash and why would I need one so soon after purchasing a new vehicle?

Like others posted your vehicle is a computer on wheels. A re-flash is a software update to the vehicle's PCM/ECM that governs engine operation, transmission function, emissions control, etc. Even electrical systems/functions in today's vehicles are run by a computer (Body Control Module)

Good advice so far.... if you're looking for a good brand specific forum check out ramforum.com I checked out several when I got my Ram and this on is a great group of folks.

BTW... nice 5th wheel. I just bought the exact same one a month ago and am super happy with it.

what's with the odd gear ratios that Ram is using in their trucks - seems like I read a lot about this lately (mostly on the 6.4 though)?

The 66RFE ram uses behind both Hemi engines in the HD line has the same gearing as the 68RFE behind the Cummins. The gearing is numerically lower than the ratios found in both the Ford and Chevy gas transmissions. The Ram would benifit from higher numerical differential gearing to compensate, but 4.10 is the highest available unless you go to chassis cab. 4.44 would be sweet.

I vote for a reflash.

I had my F150 reflashed under warranty a couple of years ago. Sometimes, when the tranny was warmed up, a manual downshift from 4th to 3rd would cause a huge clunk. It felt like I hit something. Initially the service advisor told me to not manually shift the truck (WTH!). I told them this is normal, especially when engine braking and to not tell me how to drive my truck. Anyway, Ford recommended reflashing (or whatever the term is) the transmission, and wouldn't ya know, it was fixed. It actually slightly changed the overall shifting dynamics for the better.

Still, I will occasionally surprise my truck with the slow-and-go maneuver and it jerks while searching for a gear. I try to avoid this by coasting a split second before gently applying the accelerator.

steadypraying426 It happens ever so often but today was a biggie. I was rolling to a red light foot off of the pedal and then the light turned green so I push on the gas to continue driving, then it happens. My truck jerks back and forward as if my engine just fell out or something. Truck only has 10k miles on it now. It's like the transmission is slipping hard. Anyone know what this is all about?

Cummins12V98 wrote:
It is NOT a problem. You are at that moment where it drops into 1st that in reality is like having a granny low then immediately it hits 2nd so it causes a jerking motion the harder you are pushing the go pedal the more noticeable it is. It's not slipping and the engine is not falling out.

These Aisin's act a lot like a "built" trans, that is a good thing.

Really, a good thing? OP, I suggest you take it in and have the dealer look at it.

Bigfoot affair wrote:
steadypraying426 It happens ever so often but today was a biggie. I was rolling to a red light foot off of the pedal and then the light turned green so I push on the gas to continue driving, then it happens. My truck jerks back and forward as if my engine just fell out or something. Truck only has 10k miles on it now. It's like the transmission is slipping hard. Anyone know what this is all about?

Cummins12V98 wrote:
It is NOT a problem. You are at that moment where it drops into 1st that in reality is like having a granny low then immediately it hits 2nd so it causes a jerking motion the harder you are pushing the go pedal the more noticeable it is. It's not slipping and the engine is not falling out.

These Aisin's act a lot like a "built" trans, that is a good thing.

Really, a good thing? OP, I suggest you take it in and have the dealer look at it.

The Aisin trans is not your typical slush box trans that has slippery smooth shifts. They are firm and the op had a situation that can happen when there is such a difference in ratios between 1st and second. Like I said with the Aisin in first it's like Granny low with a stick shift.

Op take it to the dealer if you want, please let us know what they say.

Cummins12V98 wrote:

Bigfoot affair wrote:
steadypraying426 It happens ever so often but today was a biggie. I was rolling to a red light foot off of the pedal and then the light turned green so I push on the gas to continue driving, then it happens. My truck jerks back and forward as if my engine just fell out or something. Truck only has 10k miles on it now. It's like the transmission is slipping hard. Anyone know what this is all about?

Cummins12V98 wrote:
It is NOT a problem. You are at that moment where it drops into 1st that in reality is like having a granny low then immediately it hits 2nd so it causes a jerking motion the harder you are pushing the go pedal the more noticeable it is. It's not slipping and the engine is not falling out.

These Aisin's act a lot like a "built" trans, that is a good thing.

Really, a good thing? OP, I suggest you take it in and have the dealer look at it.

The Aisin trans is not your typical slush box trans that has slippery smooth shifts. They are firm and the op had a situation that can happen when there is such a difference in ratios between 1st and second. Like I said with the Aisin in first it's like Granny low with a stick shift.

Op take it to the dealer if you want, please let us know what they say.

The OP real issue is he is pressing on the Gas, my Ram has a Throttle!