Here's a place to buy gears.

Gears - Designatronics Inc.

My issue is that I don't know what size gears to buy and mine are too messed up to count the teeth. Odo Gears charges a lot (more than I'm willing to pay) for their knowledge.

Is the electrical pick up for the speedo dependent on the differential ratio? My 84 reads too slow and different diff ratios (incorrect pick up) would account for that.

There is a helpful thread I think titled "Fix your speedometer for pocket change"

__________________
85SD 240K & stopped counting painted, putting bac together. 84SD 180,000. sold to a neighbor and member here but I forget his handle. The 84 is much improved from when I had it. 85TD beginning to repair to DD status. Lots of stuff to do.