1969 muncie 4spd id tag

[john302]

Does anyone know if the transmission id tag is different from one gear ratio to the next?Because with the different gear ratios the speedo gears would be different. Need to find out what the id tag would be for a z/28 m20 with a BV410 rear. Does anyone have a z with this combo that still has there original id tag? Also do I need a speed reducer? thanks John

[6667ss138]

3946797 is for RPO M20 with Z28
3946798 is for RPO M21 with Z28
3950318 is for RPO m22 with Z28

I don't believe there were different numbered tags based on the rear axle ratio but someone will correct me If I am wrong.

[Stingr69]

The speedo gear was matched to the specific vehicle long after the tranny was assembled so no need for a different part number.

[L78 steve]

I believe The above tag numbers go for Z28 and L78.

[69Z28-RS]

I believe The above tag numbers go for Z28 and L78.

Why would an SS with a 350 ci engine or even an L72 engine need a different part number for their M20 or M21   Or were you just referencing the M22 trans?

[KevinW]

Hmm, looking at the AIM, UPC M20-A1 has the following list:

3950376 - L6 (assume Saginaw)
3950378 - L65 & LF7 (assume Saginaw)
3950356 - L48, L34, L35 & LM1 (assume Muncie)
3946797 - Z28 & L78 (Muncie)
3950316 - M21 w/L34 (Muncie)
3946798 - M21 w/Z28 & L78 (Muncie)
3950318 - M22 w/Z28 & L78 (Muncie)

[69Z28-RS]

I guess my question has been answered, but I still don't understand....??

[Stingr69]

Keep in mind, M-20 does not always mean "Muncie".  On a 6 cylinder, or base V8 you would have a 4-speed "M-20" and get a 4 speed Saginaw tranny.

[69Z28-RS]

Ahhh...   Yes, I forgot that..   Thanks! 

[jdv69z]

The speedo gear was matched to the specific vehicle long after the tranny was assembled so no need for a different part number.

So when was the speedo gear installed? On the assembly line? So was it called out on the chassis broadcast sheet?

[L78 steve]

The reason the tag numbers are different for the solid lifter engines is the deeper rear axles. They required the small speedo DRIVE gear.

[L78 steve]

Does anyone know if the transmission id tag is different from one gear ratio to the next?Because with the different gear ratios the speedo gears would be different. Need to find out what the id tag would be for a z/28 m20 with a BV410 rear. Does anyone have a z with this combo that still has there original id tag? Also do I need a speed reducer? thanks John

I had this combo and it would not use the reducer. It would the 797 tag with the natural colored or yellow 24 tooth 3860347 driven gear.