1982 359 Peterbilt

@062 ...Thanks for looking that up.

@82 pete ...Monday I'll dig around in some of the unused corners in our office storage. We might have a couple of boxes of those charts. If so we'll figure out a way to get them to you.

 

I had an 83, and the speedo and tach drive were both cable driven. It was an easy and inexpensive fix to change the cable. The back of the speedo had a square drive hub that the end of the cable fit into. The end of the cable had a pressed on square drive piece about an inch long that fit into the socket on the back of the speedo.

You might check to see that the cab le turns while moving. When they get bad the gauge will start to jump a lot until either the cable brakes or the drive head is worn out to the point the drive spins inside.

 

Good looking fleet truck. Restoration project? Classic fleet bumper.

 

Back when I was working on old bikes, Palo Alto Speedometer was respected.

 

That's what I'm thinking, you need a specialized shop that repairs gauges. Probably a few of them on Google. I bet it will be a mail-it-in type of deal, not a place that's likely in your town. Probably has nothing to do with trucking either.

Here's one:

http://dandmrestoration.com/services/clusters/

First hit on Google