odometer
 

neither my trip odometer or the odometer in speedometer are working.are they connected.thanks,

What model do you have ?

odometer
 

it's a '85 300dt. thanks,luke

123's are notorious for slipping odometers, but the speedo continues to work. My guess is you have a broken cable, which drives both. You would have to remove the cluster by pushing it out from behind and then disassembling the lights and speedo cable. Replacing the cable is an easy dyi project. Use the search, there are lots of posts, especially in the diesel form.

Good luck!

If your speedo is working then the internal drive gear is free spinning on the number shaft. There are descriptions in the archives for repair techniques including pictures.

Basically one must remove the cluster, remove the speedo from the cluster and do various disassemble techniques depending how you decide to fix it.