After replacement of rear subframe, on occasion putting into First or Second gear makes the car go in reverse ... why?

[MickeyP]

We recently had the rear Subframe replaced with a new subframe. I picked up the car couple of days ago, and it drove well. This afternoon, when my wife put the car into First Gear, the car started reversing instead. She then tried putting it into Second Gear, and the same happened, the car once again tried to reverse.

So it was like it had not disengaged the reverse, even though she was putting it into First / Second gear.

So she switched it off for some minutes and then retried. This time it seemed to have reset itself and behaved.

If this was to happen at a traffic light, we'd be going into the car behind us, so it seems very unsafe.

I will speak to the Mercedes garage which did the work, but can anybody see what may be happening?

 

[W1ghty]

We recently had the rear Subframe replaced with a new subframe. I picked up the car couple of days ago, and it drove well. This afternoon, when my wife put the car into First Gear, the car started reversing instead. She then tried putting it into Second Gear, and the same happened, the car once again tried to reverse.

So it was like it had not disengaged the reverse, even though she was putting it into First / Second gear.

So she switched it off for some minutes and then retried. This time it seemed to have reset itself and behaved.

If this was to happen at a traffic light, we'd be going into the car behind us, so it seems very unsafe.

I will speak to the Mercedes garage which did the work, but can anybody see what may be happening?

I think they put the gearbox in backwards .
Seriously though I have no idea , but good luck with the garage and let us know how you get on . MB’s work should have a 12 month warranty .