since i got the truck a year ago, the speedo jumps up and down by about 20mph. Now my odometer stopped, just blank, but the speedo still works(marginally as usual)...Is this related and what can i do to fix it. Since the od is digital is there a fuse or connection that i can check?

 

 

There is a fuse under the dash that controls the OD. However, when this fuse is removed, the speedo doesn't work either.