Automatic Transmission "thump"?

[TexasChuck]

When cold, right out of the garage, sometimes only, I hear and feel a thump when stopping, almost stopped, downshifting into 1st. Anyone have any knowledge on this? 2014.... 15500miles.

[Trips]

The 7AT is notorious for doing that.

The simple fact they are always looking for the higher gearing to get better gas milage is another annoying thing.

[Wonka2581]

I would avoid downshifting into 1st gear.. I also have a 7at and never downshift into 1st. Lowest I'll go is 2nd.

[FPenvy]

Originally Posted by TexasChuck

When cold, right out of the garage, sometimes only, I hear and feel a thump when stopping, almost stopped, downshifting into 1st. Anyone have any knowledge on this? 2014.... 15500miles.

Originally Posted by Wonka2581

I would avoid downshifting into 1st gear.. I also have a 7at and never downshift into 1st. Lowest I'll go is 2nd.

soooooo recently mine has developed the "thump" from 3 to 2.

i drive 99.9% in manual mode. i shift every gear except 2 to 1.....never downshift into 1st. let the car do that on its own.

however sometimes i will also let it downshift from 3 to 2 on its own at low speeds coming to a stop.

now from 3 to 2 if the car does the shift it thumps. BUT when i do the 3 to 2 shift manually on the shifter or paddles there is no thump.

i also got scared that i blew something so i did a tranny flush and it made no difference in the thump EXCEPT the thump only happens when the car is warm and operating temp. cold temp beginning of the drive the 3-2 auto downshift feels normal.

[Wonka2581]

Have you taken it to the dealer? Have them look at it?

[FPenvy]

Originally Posted by Wonka2581

Have you taken it to the dealer? Have them look at it?

i let the dealer do the fluid change since i don't have the specific tools to preform that since it's a sealed system and you gotta drain, fill a little, run it, fill a little, run it, etc...

i never ever let the dealership touch my car. well except the warranty steering lock they replaced. obviously couldn't do that on my own lol

[Wonka2581]

I hear ya, I would let them check it out..

[FPenvy]

Originally Posted by Wonka2581

I hear ya, I would let them check it out..

i think it's fine since it seems like an issue with the ECU downshifting it at the wrong time causing the thump. when i shift the car down into 2nd there's no issue at all.

if something gets worse then maybe i'll have it checked out but not by a dealer.

[Wonka2581]

Do you have a tune?

[FPenvy]

Originally Posted by Wonka2581

Do you have a tune?

yes the ECU and TCM are both tuned but that was a few years back so i feel like that's not the issue.

[Wonka2581]

Originally Posted by FPenvy

yes the ECU and TCM are both tuned but that was a few years back so i feel like that's not the issue.

Hmm well keep us posted..

[FPenvy]

Originally Posted by Wonka2581

Hmm well keep us posted..

wont be an update unless it eventually blows up lol

even after the thump i went to the drag strip. thing rips perfectly still with no issue.

like i said the only time it's concerning is when the car shifts itself from 3 to 2 and the car is at operating temp.

hence why i did a fluid change thinking the fluid just went thin. i thought it would help but still there which makes me wonder if they actually changed it or just charged me. being a dealership not actually preforming the work but charging is a completely possible.

[danelonson]

My 2012 AT does the "thump" from 2nd to 1st sometimes especially when warm. Sometimes it's really bad, the first time it happened to me I thought I got rear ended from the strong jolt it caused. Don't know if it's normal but mine did it since day 1.