I'm guilty of doing the same thing - goes back to the days when I drove my 240D manual. I've been lucky, though in that I set my parking brake religiously, which has prevented (so far) any rolling back. This annoys my wife to no end.

The "shift lock" found on the '90 and later models seems to address this problem. Basically, it's a cable going from the ignition tumbler to the shifter, which prevents removing the key unless the car is in Park. I thought of this as a vanity feature, but I see value in it now. I have a steering column from a '90 300SEL, which has this. I'm considering adding it to my '86 SDL, since I'm also changing out the wheel. If I do so, I'll let you know how it goes.

- Casey

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Casey Cooper
"From a long line of Mercedes ownership"

'86 300SDL 250K miles (Gone, but not forgotten); best diesel I have ever driven, too bad about the Achilles heel.

'81 240D 370K miles (Sold to my brother after 9 years and 150K miles of reliable driving!)

[Five other Mercedes in family clipped for less length.]