Hi Gentlemen,

I'm coming into this conversation late but am having speedometer issues too - my conclusion is that I was missing a part in the transmission too because my new speedometer cable does not turn when the truck is being driven (but will turn by hand when not connected to the transmission).

My question is, If I get one of these gears or drivers you mention, is that something I can put in relatively easily from in the cab with the floorboard out? (rather than needing to disassemble the transmission).

Here is a picture of what I see on my transmission connection if it helps. https://goo.gl/photos/GxJN1rrbF88B68t98

Thanks,

Doug

1940 Chevy 1/2-Ton
In the Stovebolt Gallery
Lots more pix of my truck