speedometer and overdrive not workin
#22
#24
Tooth count is how the speedo is calibrated. If you have larger than stock tires, or are going to change gears in the diffs, NOW is the time to get the right ones for that exercise. I think further down the page that I linked to earlier, or, from a link on that page, there is a chart that goes by tire size, and gear ratio, so you can get the right combination for your application.