Tranny thunk

[Alexpaul09]

In my 6.4 when taking off from a stop if I let off the gas relatively quick anywhere from 30-60mph it makes a pretty loud thunk noise in the tranny and feels like it pushes the truck for a second. Anyone else have that?

 

[SETEX 6.4]

In my 6.4 when taking off from a stop if I let off the gas relatively quick anywhere from 30-60mph it makes a pretty loud thunk noise in the tranny and feels like it pushes the truck for a second. Anyone else have that?

Mine does that too sometimes but I feel it's more the combined play in the transmission, transfer case and rear axle.
It's as if all that combined play just perfectly unloads at the same time.
Just my thought.

2014 Ram 2500 Mega Cab 6.4 Hemi 4:10 Gears Ram Boxes 35x12.50R18 on Factory Wheels
Sent from my SAMSUNG-SM-G891A using Tapatalk

 

[KrisK]

In my 6.4 when taking off from a stop if I let off the gas relatively quick anywhere from 30-60mph it makes a pretty loud thunk noise in the tranny and feels like it pushes the truck for a second. Anyone else have that?

Yes, my 2017 6.4 does the same thing. Dealership said it’s normal. Granted it’s the same dealership that says the front driveshaft doesn’t need to be lubed, so I don’t fully trust everything they say. Mine has done it from day 1.

 

[McBroom]

I haven’t noticed that in my truck. But I also have a bilstein shock on top of the axle. ASD’s too


I Love my 18 Ram 2500HD 4x4 CC
Blue Streak Pearl off-road

 

[SETEX 6.4]

My 2014 Mega has no top link shock and it has a one piece rear driveshaft.
I do notice that it does it more when in tow haul mode driving around in the city.

2014 Ram 2500 Mega Cab 6.4 Hemi 4:10 Gears Ram Boxes 35x12.50R18 on Factory Wheels
Sent from my SAMSUNG-SM-G891A using Tapatalk

 

[McBroom]

My 2014 Mega has no top link shock and it has a one piece rear driveshaft.
I do notice that it does it more when in tow haul mode driving around in the city.

2014 Ram 2500 Mega Cab 6.4 Hemi 4:10 Gears Ram Boxes 35x12.50R18 on Factory Wheels
Sent from my SAMSUNG-SM-G891A using Tapatalk

Thanks for the word help I need it often. “Top link shock” I knew you had my back.


I Love my 18 Ram 2500HD 4x4 CC
Blue Streak Pearl off-road

 

[SETEX 6.4]

Thanks for the word help I need it often. “Top link shock” I knew you had my back.


I Love my 18 Ram 2500HD 4x4 CC
Blue Streak Pearl off-road

lol
I still don't understand why some trucks got the top link shock and some didn't!

2014 Ram 2500 Mega Cab 6.4 Hemi 4:10 Gears Ram Boxes 35x12.50R18 on Factory Wheels
Sent from my SAMSUNG-SM-G891A using Tapatalk

 

[Ratket]

My 14 6.4 did it when coming to a stop, it’s like it would down shift and jump forward almost as if the injectors stayed open and put more fuel into the cylinders than was needed, I know if not on the brakes it would almost accelerate

 

[SETEX 6.4]

Yes mine is when slowing to a stop or slowing to make a turn.

2014 Ram 2500 Mega Cab 6.4 Hemi 4:10 Gears Ram Boxes 35x12.50R18 on Factory Wheels
Sent from my SAMSUNG-SM-G891A using Tapatalk

 

[zeddy]

My 2015 6.4 crew cab with that shock over the axle did it. My 2017 6.4 mega cab that doesn't have that shock also does it.

One thing I noticed on my 15 was after 14k miles it did it less and less. My 17 after 12k miles started doing it less also. After I took my 17 in for a recall few months ago, they flashed the whole truck including the tranny. Its does it more frequently now. When I took it into the dealer last week for the tail gate recall, I told my service advisor. He looked up the history and said it's most likely from the flash, its relearning. He said if it continues after 5k miles to bring it back.

 

[mtofell]

Yep - mine does that and worse. All normal according to the dealer. Of course I wholeheartedly believe there are two sentences in the Ram service writer training manual:

Will the vehicle move? If yes, inform customer it is operating normally
Is the vehicle on fire? If no, inform customer it is operating normally

 

[22hemi13]

What is this top link shock y’all speak of? FWIW my 2014 with 5.7 does that hard shift from time to time too if I let of quickly and it’s cool out. Also have the clunk from take off. Everything has been serviced and no issues. Truck has 96k on it now. I think these dang trucks are just clunky. My previous f150 had a cluck also. Clunk clunk clunk clunk now for years lol

 

[SouthTexan]

OP, what you are feeling is probably your torque converter locking and unlocking. The 68/66RFE does not respond that quick so if you decelerate shortly after it locks then it will cause that clunk and bucking until it has enough time to transfer the fluid to unlock it. This should go away over time as the transmission learns your driving style. However, if you are one of those that drives like a grandpa one day and like you stole it the next then it may never learn your driving style because it takes some time and miles before adapt.

 

[McBroom]

OP, what you are feeling is probably your torque converter locking and unlocking. The 68/66RFE does not respond that quick so if you decelerate shortly after it locks then it will cause that clunk and bucking until it has enough time to transfer the fluid to unlock it. This should go away over time as the transmission learns your driving style. However, if you are one of those that drives like a grandpa one day and like you stole it the next then it may never learn your driving style because it takes some time and miles before adapt.

Now I know why mine don’t do that... I drive like a ole blue haired geezer... 40 mph in the left lane. [emoji23][emoji1787][emoji23]


I Love my 18 Ram 2500HD 4x4 CC
Blue Streak Pearl off-road

 

[HammerHead]

My 2018 6.4 does this, but I think it's the rear diff. Locking out 6th gear in city driving helped A Lot.

 

[Fitz-0518]

My 2018 2500 6.4 had this type of shift down condition for the first 1000 miles. Once the learning module completed its role, the trans shifts perfect up and down. No lumps. But we disable MDS around town and in tow/haul. I believe MDS adds to the trans shift clunk.

 

[sm10]

I have the same clunking going on in my 2016 power wagon. I bought it a couple of months ago with 26k. It clunked pretty bad when I first bought it and seemed like it got a little better over the next 1k-2k miles. I had my truck in the dealer a few weeks ago for some issues and the clunk was one of them. I got the truck back and its clunking as bad as day 1. They did do the tranny solenoid recall so they may have flashed the computer. So maybe the truck does need time to learn your driving habits. I'm taking it back in today for the clunk and a couple of other things so we'll see what they say.

 

[14RAM4X4]

I noticed mine like to clunk overly loudly when going into gear from Park. Does it in reverse and louder going into drive. The truck also bucks a bit. Even if I'm mashing the brake pedal. I figured it's the torque converter. I haven't really noticed it doing it when driving. Every once in a great while when downshifting. But it hardly ever clunks when downshifting anymore. Currently a little over 40K miles.

 

[mohemipar]

Never had this on my truck. I run mostly with MDS off.

I've actually experienced more thumps with the various ZF's I've owned. Always before they warm up.