The speedometer on my Champ Truck started to act erratically so I thought that the cable needed lubricating. I reached in behind the dash and unhooked the cable from the speedometer head. I removerd the cable and carefully lubricated it ( a messy job) and re-installed it.

It still acted erraticlly so I bought a new cable and shaft assembly and put it on. The speedometer acted worse. Then it stopped completely and I knew what happened. The new cable had sheared off. The question was why.

Reading on the internet I found that other people had the same problem. Our cars are 50 years old and the speedometer head needs to be lubricated.

So I pulled off the speedometer head and there is a small hole where the cable attaches and the brass shaft connector is supposed to rotate freely. Mine was completely siezed. I little judicious work with an oil can ans a screwdriver that fitted the sheft connector and it finally spun freely.

Reconnecting everything and it now operates as it should.

The purpose of this story is; if the speedometer needle bounces around pull the speedometer out of the dash and lubricate it. It will be like new.