Speedo not working 1993 D350

[BJ321]

I have a problem with the speedo not reading correctly. At 40 mph it'll read 16, 50 mph it's saying 18 or 19 and at 60 mph it'll say 21 or 22. The odometer seems to be working ok. I've put a speed sensor on it, checked the gears and just about everything else. At a loss for what to try next. I'd sure appreciate any advice, ideas or instructions. Haven't had the truck long...
I'd also like to get recommendations on speedometer repair if anybody knows any. I'm in the Houston area.
Thank you

 

[DVolk]

Need a little more info .
Is the stock size diameter tire on the truck ?
The generator , electric device that the speedo reads could be bad

 

[cerberusiam]

Little electric motor the runs the speedo and it s gears are messed up. Need a speedo repair shop that can actually work on these older units, getting hard to find anymore.

 

[DVolk]

Their is a shop in Portland, Or that works on Guages

 

[AnonEd]

I recently had mine done at North Hollywood Speedometer...in LA and not cheap but came recommended.

 

[Capt. Methane]

I don't know if you're comfortable trying to tear into the speedo yourself but these guys might be able to help you out with parts

https://www.odometergears.com/products/Chrysler-Dodge/All/5