Been dere dun dat!

Dont use vise-grips or other grip pliers. if the hex cant get it off, the pliers have even less chance, plus they will tear up the head of the bolt. my drain plug was soo tight that it ruined my hex wrench! (it was a cheap set) so we eventually had to use an EZ-out which worked after a while. make sure you have the new plug before you ruin the old one!

the size of the drain plug varies between models, but its in the factory service manual or listed in fast-lane.

__________________
1991 300 D 2.5 Turbo, 220k
also in the family:
1981 240 D 185k
1991 350 SD 185k
2006 S 500
2005 SLK 350