XVG

Hi all,

I have a 2024 GLE 450 and I recently started to experience some harsh downshifting while breaking, for the last 2-4 weeks. Vehicle is 7 months and has 8,500 miles.

It happens around 40% of the time, but only if the car was in 5th gear or higher. Otherwise either it doesn't happen or it's so mild that I don't feel it. If you put the vehicle info screen with acceleration and braking you can see the braking going from 8% to 16% or so when this happens.It looks like the car is deliberately using 5->4 (and 5->3!) to apply a good bit of extra braking. But it's so much that is not smooth and gets annoying. In my case it lasts until coming to a stop, so I am not sure if it's the transmission or the whole braking behavior/system/programming. It seems more pronounced when there is a car in front of me, or there is a stop sign, so maybe? (I have driver assistance package). This may be totally placebo and instead it may be related to the current speed before braking. I am not sure if the assisted braking uses radar/stop information or not. I know the regen does, cranking the regen if there is a slowing vehicle in front.

I'll mention this to the dealership next time the car is there and I have a loaner. It would be great if they can reset the parameters to what it was before.

I've seen several posts over the years complaining about this behavior – I wonder if other folks with 2024 GLEs are experiencing this.

graffixnyc

You can try resetting the transmission adaptations to see if it helps. It will then re-learn based in your driving style. I did this on my 2024 350 and noticed a difference. I don't have the issue you've described exactly, but I have had an issue where when I'm slowing down approaching a red light, I'll get a little buck once and a while, Like a jolt. It was something I was going to bring up at my first service appointment. It's probably happened 2 or 3 times since I bought the car in March.


To reset the transmission:

1. Put the car in accessory mode while not running (all the warning lights lighting up on the dash, pressing the ignition button twice).
2. Hold down the accelerator all the way floored for about 10 seconds.
3. While the pedal is still pressed down, turn off the ignition and keep the pedal pressed
4. Keep the pedal pressed down for about another 2 minutes (some say 10 seconds after turning the ignition off but I saw a video where he said to hold it for two minutes, even verified through an application that values for the transmission adaptation were updated after the process).
5. Take your foot off the gas, then turn on the car, take it for a ride and go through all the gears

When I did this, I actually heard something click a few times during step 4. I really did notice a difference after. The car seemed to be more peppy/responsive. My 2024 350 was bought slightly used with 1,021 miles. The original owner had it for 2 weeks and traded it in and then it sat on a lot for a month and a half and I'm sure was test driven by different people so I'm sure the adaptations were all over the place.

I'm not sure if this is the same process the dealer does to reset the transmission or if they do something more involved (probably the latter)

XVG

This is good stuff. Thanks for sharing. I'll try it out soon.

The jolt that you describe is actually what I am experiencing, but much more often than you – pretty much is 50% of the times that I come to a stop / red light. Especially when stopping from <= 40mph. It feels like the shifting point for the 4th gear is out of range.

Lucky 777

If you put the car in ECO mode which allows the car to coast, does that help?

XVG

I've mainly driven the car in Comfort since I started noticing this, and I have been able to replicate the issue in Sport too. I briefly tried Eco and it was less noticeable, but I have to do a longer drive in Eco to be able to judge for sure – sometimes it will be ok for a few stops and then happen in the next one.

In any case I didn't notice any of this during most of my ownership. I am pretty sure it's something "learned" over the last 3-4 weeks.

Sieveboy

experienced since new in my 2021 GLE450, the regenerative braking and transmission downshifting are not very well executed, it's clunky as hell snd a real disappointment in an otherwise nice vehicle.

really spoils what is otherwise a great engine

cypress822

I have had this issue since first day with my 2021 GLE 450
Mercedes has no idea how to fix it.
I have had it into service numerous times without success.

W205C43PFL

There's a recall, not sure if it is related: https://mbworld.org/forums/gls-class...gle-450-a.html

Streamliner

It’s funny, but I came to V167 to post how much I am enjoying the “Bare Bones” 2024 GLE350 loaner I have been driving, when I saw this thread. MBUSA bought back my 2020 S560 sedan due to a very harsh 3-2 downshift that “developed,” several months after I took delivery. The dealer was instructed by MBUSA to replace the transmission and torque converter, which they “supposedly” did (I don’t believe it), but they were never able to fix it. They refunded every penny I paid for the car.

Anyway, this 2024 GLE350 is a very easy vehicle to live with and I particularly enjoy the very smooth shifting transmission. Go figure. Best of luck to the OP!

HotRodW

We've dealt with the harsh downshifting on-and-off since shortly after we took delivery. One dealer tells us it's normal, one dealer acknowledges it but then says it's working as designed. Nobody can explain why some GLE's with the identical powertrain having not even a hint of a problem, which I find odd for something they claim to be "working as designed".

While not admitting to it be broken, the transmission's software has been updated multiple times and adaptations reset repeatedly, but the problem remains. Curiously, the issue had almost completely gone away earlier this year ... and then the transmission's software was updated for the recall, and the darn thing is back to shifting like it's broken - which it clearly is. I've given up on it (and I've given up on Mercedes). My wife is more tolerant than I am, so she's driving the GLE. For now. I give her a year before she throws in the towel, too.

jgc02

I think the harsh downshifting is due to the mild hybrid regeneration. Had it in both my 2020 GLS450 and my current 2023 GLE53.

randsny

Can the regenerative braking be disabled? It is annoying as hell to coast to a stop and feel the car jerk and jerk all the way to the stop. My wife's GLC300 is smooth as glass and much more enjoyable to drive.

Streamliner

Isn’t there a good lawyer here somewhere? This is such a HUGE issue, affecting most every class of MB. There really should be a class action lawsuit.

cypress822

I have given up, and am going to buy a new car. Hate to do it.

mikapen

I think that's the best solution for you, except that you'll need to buy an old car to avoid all the fed required Nanny's.

mikapen

I don't think you're talking about regenerative braking being jerky. It's really smooth.

And in my opinion, the only problem with downshifting is that the car's algorithm remembers that time you were aggressive, and retains that rev-matching-downshifting pattern longer than it might.

Once you floor it, it seems to wanna be a sporty transmission for an hour instead of 5 minutes.

HotRodW

I don't think nannies have anything to do with it. All cars have nannies. This is a Benz-specific problem.

I'm not buying that. The harsh downshifting doesn't last for an hour. For us the problem is intermittent but more on than off, and lasts months. If anything it also worsens with each adaptation reset, which is the opposite of learning aggressive driving. Besides, if it were the adaptive transmission, every GLE would experience the downshifting issues. In fact, all 9-speed Benz transmissions would, and they just don't. There are plenty here who have reported having zero problems, and at least one member had a GLE with the problem, and one without. Our GLC's 9-speed never once acted up in 50k miles.

Frenetic

Mercedes’ transmission are terrible. I’ve owned and driven two of them back-to-back in my GLE53 and now S class and they both “clunked” on the 3 to 2 downshift and will occasionally bog down and lag on kick-downs. And I followed the manufacturer’s break-in procedure to the T on both. Trashcan transmission.

cypress822

I wonder if the GLC does this also???? Anyone know?

GibbsKnot

Mine has started doing this as well over the last couple of weeks. It downshifts harshly (jolts) from 5th to 4th on deceleration only. It’s very noticeable and does it every time. Changing the driving mode or manually shifting does not make a difference.

It will upshift smoothly from 4th to 5th. It will also downshift normally from 5th to 4th, but only if accelerating.

I tried the “relearning” procedure someone posted. It doesn’t make a difference; perhaps, I did not do it correctly. I have an appointment to take it in soon. We will see what the dealerships says, but something is clearly wrong.

graffixnyc

This is one of the videos I saw on resetting it. He uses a key, but you can just press the start button twice so that all the warning lights are lit up on the instrument cluster.

HotRodW

It works for resetting the adaptations, but that isn't a solution if the learned adaptations aren't the problem. Some members have claimed the reset improved or fixed the problem. I've had mine reset at the dealership three times and tried it myself twice, and not once did the downshifting improve.

W205C43PFL

In that case, will have to just request for a "Forced adaptation" and hope it does it: https://mbworld.org/forums/s-class-w...ml#post7961182

HotRodW

Did you have the transmission recall completed? The recall process includes a transmission software update. My paperwork doesn't mention specifics, but the service manager told me he was confident the software update was "inclusive", and so the adaptations should have been reset. Of course he didn't say it with any real certainty, and I'm not convinced he had any idea what he was talking about. But whatever they did actually made my downshifting worse.

GibbsKnot

I do not think a recall was done that affected the transmission. The only recall that has been applied according to my documentation is Campaign 202402004, which appears to be related to MBUX.

This is for a 2024 GLE 450 by the way. In any case, I will make sure to provide an update here once I hear back from the dealership. I will keep the “Force Adaptation” request in my back pocket.