Speedometer Jumping Around at 40 MPH Only

[70deuce]

My speedometer is jumping all over the place at 40 MPH. Rock solid above and below that speed. Worth messing with??

 

[Heath_h49008]

If you get a speedo cheap enough, why not? It's not going to get better.

 

[70deuce]

Heath_h49008 good point. As the truck is driven around here, most of the time its below or above that speed but annoying none the less. I would agree though its probaly gearing within the speedo itself. I will take your advise and swap another one in to see if it changes the gripe. Changing the cable is a pain in the butt but just swapping a speedometer not so much.

 

[steelandcanvas]

Grab the speedo out of that M54 you got sitting around. I know the owner, he won't notice. He always looking at the fuel gauge anyway.

 

[rosco]

Its usually always the cable. Before you replace anything, disconnect one end or the other, and pull the inside cable out. Clean it with Break Clean & a rag/paper towels. Re-insert it and as you slide it back in, re-grease it with a good light weight grease. Note: sometimes you can only pull them from one end or the other, & I don't remember which end. So I think you pull it from the top - not sure though. Too simple, not to try. But usually the bounce is the cable.......

 

[phil2968]

Yup, what he said!