If your odometer "slips a cog" you might as well epair it while you have the cluster removed to bridge the light potentiometer. Do a search here as well as the diesel forum for odometer repair, or similar topic. It is a pretty easy repair, and sounds more tedious than it is. In a nutshell, the pot meteal cog is a press fit on its shaft. Over time it get loose and slips. Remove the shaft by pressing it out using a same-size shaft to keep all the wheels in place. I used the shaft on which the reset mechanism pivots. After you have the shaft out, you need to slightly deform the shaft where sits the metal cog--some use a small punch mark, I used a set of vise grips to "knurl"it slightly. Replace the shaft, and you're done.