greasykid

My 2015 ML250 has about 2200 mi on it & has recently developed an occasional hard UPSHIFT 1-2, 2-3, 3-4. Usually when accelerating @ a reasonable pace.

Has anyone experienced this? Any TSB's or corrective info?

Angelo250

Hi,

I am having similar problems with my 2014 ML250.

Did you have it fixed ?

Thanks Angelo.

greasykid

No. Have not taken to dealer yet. It only happens randomly. Just returned from a 2.000 mi trip. Almost all highway speeds so no problems. Might add that mpg was 33. Last leg of trip--340 mi.thru mountains was 35.6 mpg mostly @ speeds in the low 70's. Fantastic.
May wait till 1st A service before going to dealer.

ChuckinTucson

I was reading elsewhere on this forum on how to reset the transmission. Do the following and see if it helps:

If you have Keyless Go,
Press the Start button twice (without your foot on the brake)
Press the accelerator all the way to the floor and hold for 10 seconds
Press the Start button again (turns it off)
Release accelerator
Wait 2 minutes and then start car and drive

If you don't have Keyless Go, just turn the key to the second position just before actually starting the car and follow the above procedure.

DUTCH

Does that car still have the 7G-Tronic transmission? If so, it's been a feature of the tranny since 2007.

greasykid

Have done "RESET" previously. Some help-but not 100%. On my long trip twice when I slowed down almost to a dead stop & then tried to accelerate NOTHING happened for what seemed like a second or so--then it took off. Made an appointment for this coming Friday @ MB re. this.
Anybody else had this? I call it the DEATH PAUSE. I had this problem 30 yrs ago w/a Volvo. Very scary-Problem was never solved.

gkgeiger

Sounds like throttle by wire delay. Mine does that sometimes.

dgiturbo

Lots of vehicles are doing this "death pause". My '13 RAM does it too and over on that forum we call it the "dead pedal". It is programmed into the ECU to give a slight delay under sudden stomps of the accelerator, to avoid a large amount of torque to hit the tranny suddenly. More of a warranty preserver on the manufactures part. Dangerous and scary for the owner/driver. Try applying the accelerator a tad slower, and only to about 3/4 way down.

And yes, some of this ECU programming ("torque management" if you will) also affects how it upshifts with the diesel motor. Seems like manufactures are afraid of diesel torque on their trannys. They program them for smooth shifts with the lower torque of a gas motor, and the high torque diesels get to feel the harsher upshifts.