frostsdad

Hello,
I have a 2016 S550 4matic that I bought as a cpo. I’ve had it 3 years and driven 22k miles. Currently has 72k. Had extensive maintenance history performed at dealers only. Previously, I had a 2013 S550 which I loved - should’ve kept it but wanted to upgrade to the newer body style.

I’ve noticed harsh downshifts especially when the engine is cold (just started for a few miles) mainly downshifting from 4 to 3.

under cpo, during the last 3 years and 23k miles, I’ve had the following performed:

- shift adaptations performed and continued to have a minor “clunk” when the downshift occurs not under acceleration.

- CPO warranty covered replacing the trans and torque converter, this included new fluid, and I had the fluid changed as per maintenance schedule previously.

- I still noticed the clunk a few months ago and took it to the dealer during regular maintenance, they replaced the valve body, did a fluid change and adaptations.

- I'm still noticing the issue - is this common and should I just assume I won’t have issues down the road? I didn’t have any of these issues with my w221 (2013).

carlosinseattle

https://mbworld.org/forums/s-class-w...ting-w222.html

as.thompson

My 2016 has a sometimes harsh downshift from D5 to D4, usually when cold. Work on it by the dealer under warranty improved, but did not eliminate, the problem. Others have commented on the same issue. So it isn't just your car, it's a characteristic of that transmission.