SPEEDOMETER PINION.

Dick Koch · Post by **Dick Koch** » Tue Nov 17, 2015 8:31 am

Hookay - here's the sitchuation. My GPS says 65 MPH and my speedometer says 80 MPH. With a little research in the parts book I found out with a 3:31 to 1 differential you need a 20 tooth pinion part # 1636409. I removed the pinion housing from the tranny and found I have a 17 tooth pinion in the car and thats for a 2:93 to 1 differential. The red pinion you see in the picture is also a 17 tooth I got on ebay years ago. I reached out to FATSCO for help and they are checking to see if they have a 20 tooth pinion.
Meanwhile after trying without breaking anything and visiting a couple tranny shops I can't figure out how to remove the pinion from the housing. Note on the end that drives the speedometer cable there seems to be a plastic piece that the pinion shaft with the tapered end fits into. I assume there is something on the inside of the housing that holds the pinion in the housing so it doesn't come out when in the tranny. I hope the pictures help.
Dick.

Mark Merritt · Post by **Mark Merritt** » Tue Nov 17, 2015 9:10 am

Dick; It looks threaded,backward thread? Lightly hold where the cable inserts (small screw driver) turn backwards? That is A puzzler. Check my thread on the trim piece I got it measured. Mark

Matthew Keij · Post by **Matthew Keij** » Tue Nov 17, 2015 9:47 am

If I remember correctly there is a washer holding the pinion in the housing.

Did you find a 20 tooth pinion? I've been looking for a while now but I have no idea where to get them.
I have exactly the same issue as you

Dick Koch · Post by **Dick Koch** » Tue Nov 17, 2015 10:26 am

Matthew - I found a 19 tooth at FATSCO complete with housing. He sold a 20 tooth the other day and the 19 tooth was the last one he had so I'm getting it. If you need a 17 tooth, I have one, the 17 tooth is for the 2:93 to 1 axle. He told me to just tap the cable end and it pops out. The 20 tooth is for a 3:31 to 1 axle.

Mark - your stainless info is posted, you will be happy.
Dick.

Matthew Keij · Post by **Matthew Keij** » Tue Nov 17, 2015 10:28 am

There was a 16 tooth in it but I replaced it with a 17.
I think I have 2 more 17's.

Looking for a 20 or I might put a 2:93 in so it will work with the 17 I have now.

Dick Koch · Post by **Dick Koch** » Wed Dec 16, 2015 8:27 am

After much research I finally found a source for Speedometer Pinions. If they do not have what you want they will make it for you. A 20 tooth pinion with keeper is $62.50.
Dick.

Northwestern Transmission Parts
www.nwtparts.com

1-800-327-1955
email: northwest@nwtparts.com

'59 Plymouth Forum