2016 GLE rumble/shudder on deceleration -SOLVED 3-10-2016
first question for the forum. i just purchased a 2016 GLE 350 4matic. when decelerating, there is a specific, brief, subtle, "double" rumble/shudder at just about 20 mph. almost immediately, the parktronic icon appears in the display. this happens EVERY time and whether or not i am braking or coasting to that speed. i would like to know if this is engineered into the vehicle and if so, what exactly causes the rumble/shudder.

i did send an email request to MB customer tech support, but they said that they did not have info available to answer and directed to the dealer. FYI, they did answer my question on back-light illumination of the headlamp switch bezel -- NOT back-lit on the 2016 GLE (if any one is interested).

i emailed the dealer with this same specific question and they need me to come for a service call. not really interested in wasting a day if this is actually nothing. for background, i had a similar experience with a 1990 4matic. there was a loud "clunk" when starting from a stopped position. since the system was very new, not a lot of info filtered down to the techs at the dealer. it took a very long time to establish that it was part of the operation of the vehicle, being the front differential engaging once the vehicle started. trying to avoid a repeat of this.

the GLE has active parking and active lane keeping.

sorry for long winded post. i would really appreciate if anyone has an answer before i trek to service. thx, ron

reposted from "new M" forum this one didn't come up before, sorry.

3-10-2016

road tested with the MB shop foreman today. he said i am feeling the clutchs during the downshift. operating as it should be. said most wouldn't notice. he went into a lot more detail as to how the trans works - made sense but i didn't take notes peter, appears that you've bent a few wrenches. you may be able to fill in if anyone needs the tech info. thx to all for observations, ron

 

In short your 2016 gle shouldn't operate significantly differently than a 2015 ml, and there shouldn't not be a shudder ... This could be an issue with your transmission, the valve body, clutch packs, or simply the software mapping of the downshift points and the adaptations.

what gear is it downshifting to... 3-2, 2-1?

The parktronic is supposed to come on (the dash symbol) but mine doesn't come on until I'm around 10mph ... I do not think the display of the P on your dash and the rumble is more than coincidence but not sure why it's displaying at 20mph... That seems a bit soon.

My first move would be test drive another 2016 gle350 on the lot and see if it does that too

 

thx peter. to be clearer, this is a very subtle event and very patterned. a quick rumble rumble and done. and it happens on the low side on 20 mph. i'm probably borderline ocd as everything jumps out at me. most probably wouldn't notice it.

i have not focused on downshift aspect as that requires more attention and therefore distraction from operating the vehicle. i will try to find an empty parking lot and see what occurs there. i will make my way to service if no one comes up with a definitive answer here. thx again, ron

 

Had a shudder on mine that could happen at any speed. It typically happened when shifting gears and actually caused the car to stall at one point. Turned out to be a bad crank shaft sensor that needed to be replaced.

 

UPDATE 3-6-2016

did some more troubleshooting. it appears that a 4/3 downshift occurs at the same time as the rumble. tried some coasting stops (neutral) and some manual shift stops (no downshift) and didn't seem to occur, although parking lot pretty rough and could have been masked. going to make the service appt this week. thx, ron

 

see op for results 3-10-2016