I've at various points heard a rumour that, around 1982 or so, MB began neutral-balancing all the OM61X engine flywheels.

There certainly are plenty of neutral-balanced flywheels out there, so checking for neutral balance would be my first step -- it's a lot less drastic than pulling the motor.

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"Senior Luna, your sense of humor is still loco... but we love it, anyway." -rickymay ____ "Your sense of humor is still loco... " -MBeige ____ "Señor Luna, your sense of humor is quite järjetön" -Delibes

1982 300SD -- 211k, Texas car, tranny issues ____ 1979 240D 4-speed 234k -- turbo and tuned IP, third world taxi hot rod

2 Samuel 12:13: "David said to Nathan, “I have sinned against the Lord.” And Nathan said to David, “The Lord also has put away your sin; you shall not die."