My odometer became intermittent and eventually quit altogether. I was told to check a gear on my automatic transmission. I understand there is somesort of speedometer drive gear connection mounted on the right rear part of the tail shaft housing, and a plastic gear can be extracted for inspection. Is the gear somewhere inside where the speedometer cable goes in? If yes, how do I remove the gear? and What do I look for? If not, could someone direct me like I was blind to the exact location of this plastic gear location? What does it look like? How is it accessed? Do I need any special tools?

I recently put in a new speedometer cable to fix a wildly fluctuating speedometer reading. The cable fixed that problem but didn't help the odometer at all.

Thanks,