I’ve been complaining about the clunky shifting in my ’21 S580 ever since I got the car. Several adaptation resets, fluid flush/filter change, software updates…I was absolutely driving the shop foreman at my MB dealership crazy complaining about the shifting.

So…a little sidebar…after a recent oil change (motor oil), I noticed that the oil level was not at the MAX level, but was in between the MIN and the MAX. It had always been right on MAX. The tech explained to me that they generally “aim” for the middle of the range, and sometimes it ends up on MAX sometimes in the middle. Nonetheless, they topped it off and it is now right on MAX. I think it just takes a little more time to get it perfectly on MAX--

Now after the oil change, it was very hot in the Boston area and I took a 200 mile trip in all kinds of traffic conditions. I couldn’t believe how smooth the transmission was shifting during this hot weather. I couldn’t feel the slightest bump or clunk upshifting or downshifting. A few days later, the weather cooled, and I was back to my clunky transmission.

Knowing that hydraulic/transmission fluid expands when it gets hot, I asked the dealer to check the transmission fluid level one more time and this time make sure it is as close to the MAX level as they feel comfortable setting it to. They ended up adding about 1/3 of a quart to just under the MAX specified value. Over the last few weeks I’ve driven in all kinds of weather and the transmission shifts as smooth as can be. I’ve even noticed that the interaction between the mild hybrid charge/power system is smoother as well.

So, if your transmission is a little clunky, you’ve flushed it, done adaptation resets, etc…try filling the transmission fluid to high side of the range just under the MAX level and see if that doesn’t make a difference. You might be surprised what 1/3 of a quart can do!

 

That is very interesting, how engine oil affects the tranny behaviour like that.

 

No, OP asked the dealer to add more transmission fluid and it fixed the clunky shift problem.

 

Oops, I read it wrong sorry about that.

 

The very sloppy shifting transmission in my thankfully departed 2022 S580 was one of the most irritating features of the car. Numerous complaints to Fletcher Jones in Newport Beach—which I believe is the largest MB dealer in the country—were always answered with the “operating as designed” B.S. I am very happy that the OP got his fixed and IF indeed this is the “cure all” for the issue, what does this say about MB service? It will be interesting to see if MB issues a TSB on this.

Having now gone electric, I am overwhelmingly hooked and not dealing with ANY shifting is an absolute delight in a luxury sedan. Just immediate, ultra smooth, virtually silent, drama free propulsion.

 

We've heard Stream.

 

One of the things that makes this website great is the fact that new members come to it everyday. To them, everything old here is brand new. Comments, criticisms and advice are constantly flowing through the threads here and for our newer members, I’m sure can be quite helpful—even if others have heard it before. For the handful of older members who seem to get immense, personal enjoyment from posting “gotcha” or “we know” remarks whenever they possibly can, it just makes me laugh. Oh well, different strokes, right?

It’s a lovely day today, so I think I’ll put the top down on my SL and go for a spin! Here’s a photo I’ve posted many times, but I bet someone here will be seeing it today for the first time. Cheers!

 

We don't need to hear the same thing over and over again off topic from somebody who no longer owns the car, and we absolutely have no interest in continuing to hear about your BMW i7 or see pictures of it in threads about the S Class. There is a great G70 forum on Bimmerpost, I know you know its there because we both post there. Talk about your i7 there. There is also a great SL forum here at MBWorld, I'm sure they would love to talk about your SL there. This is the W223 S Class forum.

 

Can I check the transmission fluid level myself somehow?

My transmission is clunky as ever.

 

Agreed 100%.

 

I don't believe so...

This could explain why some people have clunky trans and some don't. Mine can be clunky under a couple of scenarios, but its not a chronic or common thing.

 

I don't recall there being a sensor in the pan that might explain why and yes fluid level does make a huge difference to the transmission shifting behaviour. A lot of times I see, at least on the W205 and W213 forums with transmission issues was due to low fluid or fluid was worn, rarely was an actual mechanical issue with the gears, the TC, lock-up clutch, etc.

 

You need an ultrasonic measuring device that snaps into the bottom of the transmission pan, so I guess the answer is no.

 

Ah yes, yet another “new & improved” advancement in automobile design. I realize that it has been this way for a while now, but can anyone tell me why this might possibly be considered a good thing and not just another example of cost cutting? How much could they possibly save by deleting dip sticks? I know, we’re supposed to be able to monitor fluid levels via electronic sensors, but I believe that the OP’s story is a slam dunk example of how unreliable such systems can be. Yet another way the auto makers are making it ever more difficult for DIY mechanics to even change their own oil, trying as they can to funnel even the most simple maintenance procedures through your authorized dealer. NUTS!

 

I’m really curious if the fluid top-off really is a fix. I have questions about it because it’s such a stupid oversight that I find it kind of implausible. I’m not saying it didn’t fix his, but it could be a placebo or maybe the extra fluid only temporarily masks the issue at hand.

 

Although, not as important as a dip stick I have trouble understanding why almost all transmissions are manufactured without a drain plug. Granted, most refills require a new pan but a drain plug can’t possibly cost that much.

 

Remember that I requested that the transmission fluid be filled to the safest maximum level....not just "within the range" of acceptable levels. For the old school guys (like me), that would be to the top of the "crosshatch" area on those big, long transmission dip sticks--not just "within" the crosshatch area. MB apparently lists a minimum and maximum level for safe operation--but not necessarily the best performance--of 48.4 mm to 56.4 mm...and I found success pushing the 56.4 mm level.

Although I don't think the tech did this...but if guys decide to top off the transmission fluid level, it might be beneficial to do an adaptation reset. I'm just enjoying my smooth shifting, so I'm not going to go looking for trouble!

 

I mean, at least it is somewhat possible.

 

Thanks for the data.

 

With an electrified future, I guess manufacturers just gave up (and especially with the tighter regulations), people keep calling these computer on wheels that is what it is and especially true in the coming years. Most of the cars are circuit boards in a decade or two with little to no mechanical components, save for maybe the motor of course.

 

I will ask my independent MB tech his thoughts on this. I will also have him check my fluid level when he changes the oil next week.

 

Please let us know what they say; I'll be visiting the dealer next month and may ask them to look into fluid levels depending on everyone's results.

 

All the best! I guess I forgot to mention another thing besides transmission fluid, software and its self-learning properties, if it learned incorrectly, time to teach it manually.

 

Mines not bad. It does get a little confused sometimes. Mainly when rolling like through a green right turn and you pause and look for traffic and then go, it doesn’t like that pause and usually is in the wrong gear. That’s not unlike other multi speed transmissions I’ve had in other cars though. 9 gears is a lot to sort through.

 

Well described - that is what I experience as well. Smooth as silk on freeway and normal driving.