My car is a 250 4matic auto, 2014, 55k miles.
Over the past two months I've noticed symptoms that are getting worse (or I'm becoming more aware of...). When driving at a constant slow/moderate speed (under 25mph) I feel and hear what I can only describe as shunting in the drivetrain. It seems to come from the centre of the car to the rear somewhere - not from the front ahead of the gearbox. The noise/feel is subtle and disappears in the increased road noise at higher speeds. It is linked to road speed and at constant speed is fairly regular, but not totally. It just feels like there's a tiny amount of slack in the drivetrain that is being taken up and then relaxed again, even at steady throttle opening on a flat road.
So now the odd thing...
Four days ago, I went in to MB for MOT and mentioned this to them. I asked whether someone could just drive round the block with me, to advise whether there is an issue or whether "they all do that".
My car goes off to the workshop for MOT, and returns two
hours later. I'm told the technician took it for a test drive and could see no problem. "Sorry sir, but we're much too busy now for the technician to go out in the car again with you..."
So, somewhat bemused, I drive home thinking "the car will be due a service before Christmas when the warranty runs out, so I'll take it somewhere else".
But on the journey home and in the four days since, there has been no repeat of this shunting issue, None at all.
So anyone got any ideas on what they did to my car ? I just do not believe it's a simple coincidence.