The 2015 E350 212 estate has almost 120,000 miles on the odometer. I used to get it serviced at MB as part of my service plan, but when the price of the plans went up a few years ago, I switched to a local indie. They aren't experts in MB, but they've been able to fix most of the things I couldn't handle on my own.
The car was serviced and MOTd a few months ago without any problems; however, I had observed that the rear suspension had a tendency to dip when parked for an extended period, so we decided to have someone check it out. I started to notice an issue every once in a while while driving around the same time. While in sixth or seventh gear, it became the most apparent. When you gently press down on the accelerator after coasting for a while, you might feel a little 'kangaroo' effect, similar to what you would experience in a manual gearbox car when you're going too fast for the gear you're in. At the time this problem was discovered, the vehicle was not shifting gears.
Took the vehicle in for a suspension checkup; after discovering a leaking air spring, the issue was resolved. In their investigation into the kangaroo problem, they uncovered a gearbox code reading "Internal control fault at the CPU" (P060C-00). They were able to clear the code and then had the vehicle for a few days, during which time they took it for multiple test drives without noticing any problems and the error code never came back. But, I've observed that the problem appears to persist even now. Icarsoft did a scan, and it came up error-free. Additionally, I have reset the gearbox twice, but the problem persists. Not constantly, but generally speaking, the vehicle performs admirably. I could probably handle it if it wasn't going to get worse or if it wasn't an indication of some kind of impending catastrophe, but it's also not like this before and it's not normal.
I would greatly appreciate any recommendations that members may have before I return to the independent, with whom I have maintained a cordial relationship throughout the years and with this vehicle in particular. Giving it to the neighbourhood MB dealer is no longer an issue for me. I was never impressed by their service, and after just a few days I would have racked up a bill that was more than the car was worth!