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Accelo · 06-03-2022, 01:27 AM

17 PURPLE
18 BROWN
19 WHITE
20 BLUE
21 RED
22 GRAY
THESE GEARS HAVE A .780" DIAMETER HEAD AND A 1.760" STEM LENGTH.
THEY ARE FOR USE WITH DRIVE GEARS THAT HAVE AN 1.840" OD.

GM actually made two gears for the tail shaft both with an 8 tooth count but in two different outside diameters. In the early years 3 and 4 speeds these were metal gears with an interference fit on the shaft. Only way to tell for sure which one you have it to measure the OD. I know for sure my 1970 3 speed had the metal gear installed on the tail shaft. The speedometer gears were the only parts I kept from the 3 speed transmission.
Confusing isn't it?

06-03-2022, 01:27 AM	#10
Accelo Registered User Join Date: Mar 2015 Location: washington Posts: 2,162	Re: Saginaw 3 speed Speedo Drive Gear? 17 PURPLE 18 BROWN 19 WHITE 20 BLUE 21 RED 22 GRAY THESE GEARS HAVE A .780" DIAMETER HEAD AND A 1.760" STEM LENGTH. THEY ARE FOR USE WITH DRIVE GEARS THAT HAVE AN 1.840" OD. GM actually made two gears for the tail shaft both with an 8 tooth count but in two different outside diameters. In the early years 3 and 4 speeds these were metal gears with an interference fit on the shaft. Only way to tell for sure which one you have it to measure the OD. I know for sure my 1970 3 speed had the metal gear installed on the tail shaft. The speedometer gears were the only parts I kept from the 3 speed transmission. Confusing isn't it?