I have an 81 240D where the odometer and trip odometer just stopped working. Anyone have any ideas as to a fix for this ? thks.

Typical VDO
 

Brother of The benz, sgoodhart
All of us with VDO speedometers experience this failure.
The driven cross shaft disconnects from the drive shaft.
I've reassembled mine a number of times before giving up and taking it to a Service Center.
Don't do as I did, that is remove it myself.
Drive to the Service Center and let them remove the speedometer.
My cost was $99.00.
Happy Trails Beep Beep from The Spiderman in Houston!!!

Speedometer
 

Thanks for all the help. I took it out last night and am sending it to a shop to fix.

If you are going to drive a 123 without the instrument cluster, you better figure out a way to plug that oil pressure line, or you will get a rude awakening to your mistake.