Aside from all that has been said, if the fluid level is 2 drops too full, it will come out the vent on top and hit the exhaust. This only will happen at high speeds.

I would correct the fluid level first. The correct level is 10mm below the bottom line when cold, at idle in park.

Good luck.

__________________
Benzmac:
Donnie Drummonds
ASE CERTIFIED MASTER AUTO TECHNICIAN
MERCEDES SPECIALIST 11 YRS