[RooCat]

Hi guys. I recently bought a 2011 S550 4Matic with 102,000KM. Had it inspected by an indy, which passed, and it didn't throw any codes. As luck would have it, on my way home I was decelerating (not yet braking) going around 25km/h on a small uphill incline and upon downshift felt a hard "nudge". I get home and do a little digging to come across many threads (albeit mostly 2007s and 2008s) with the same problem. The symptoms outlined in these thread are exactly what I experienced. I've gone on to read in other subforums some horror stories of people having to replace the transmission/valve body (some just to find the issue is still present even with warranty replacement).

A few questions I'd be thrilled to have sorted

1. Is this common in W221s? It seems much more prevalent in other subforums than this one?
2. Is this supposed to be limited to 2007s and 2008s? I haven't seen any threads with 2011+ w221s.
3. Is this something that's going to get worse and require replacement valve body/transmission?

If the consensus is that there wouldn't be much long term damage and this is just a "quirk" I can probably live with that. But if I'm in for a world of hurt in the near future, I'd rather cut my losses and try to sell the car now. I paid $22k CAD and don't really fancy paying another 30% of that for a replacement transmission 10k kilometres down the line. Thanks in advance for any guidance you guys can provide.

 

[SilberGrauW240]

I have not followed this issue for the 221 cars, so this is just a general comment, but I would search the internet for a "transmission reset" procedure, something akin to holding the accelerator pedal to the floor for some amount of time with the car's electronics ON, but engine not running, of course. These are electronically controlled transmissions, and they adapt to driving patterns over time. It might make a difference, and won't hurt anything. If that doesn't work, you might have to pull the codes with a M-B diagnostic. One other thought: Does your car have C (comfort) and S (sport) modes? Does it happen in one or both?