Remachining a highspeed speedometer drive for a truck
 

been tinkering with this today, a 28-29 AA truck with the highspeed wormdrive. for the gear on the drive shaft that is stamped 5 1/6-1-32x6 i made a driven gear for it. Since the driven gear has 19 teeth i took one from a car that had 19 teeth. I had a junk 6.6-1 slotted driven gear so i turned the gear off the shaft and took it down to .351, the car gear has an ID of .350 so it made a good press fit. the OD of the gear was still a little big so i turned off .030 off the diameter. one could do this with a nylon gear if they are worried about wear on the driveshaft gear.
I was lucky enough to be able to find the drive shaft gear but i could not locate driven gear.

Re: Remachining a highspeed speedometer drive for a truck
 

Good work, let us know how it works. Necessity is the mother of invention!