[Leroy Daniels]

My 1991 Dodge Ram D-150 - the speedometer works correctly, but the odometer does not work. What is the problem?

 

[ImperialCrown]

Maybe a broken plastic gear on the speedometer? There have been some past posts on this if you type 'odometer gear' in the search space at the top of the page.
One possible source: http://www.odometergears.com/products/Chrysler-Dodge/All+except+Monaco/125