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                              Refresh your page F5  Last Updated: Aug 9, 2016



My Muncie M22 sounds I recorded with 3.73 gears.    



Side view id.



Muncie (left)                    Saginaw (center)                 Borg Warner (right)










Mine shown here with an aftermarket  Hurst Comp Plus. I have since changed it back to the original Hurst.

To see the OEM shifter lever clips and wave washers go to



1970 OEM Hurst Comp Plus Shifter



1970 Shifter Mount Plate







WB code for a M20. I kept the code on and painted the tranny






RPO M20/M21 gear set



RPO M22 gear set



Here is mine. I've already removed the mainshaft out but forgot to snap a pic and inserted it again, so

that's why 3rd gear looks lop sided. I needed to replace some worn parts and disassembled it.

Note the thickness of the 3-4 slider where the shift fork rides.


M22, here I've replaced my sliders with the new torque thrust sliders.

If you have worn gear engagement teeth (the part that locks into the slider), these sliders will stop the tranny from popping out of gear.

But it's best to replace both the worn gear, slider, 3 slider keys and the lock ring since the tranny is already open. The hub can be reused.



4th gear comparison




M22 10 spline with bearing retainer installed with french locks on the bolt heads




M20 10 spline



M22 counter gear

If your replacing your needle bearings in the counter gear, I like to use a cut off broom stick so

I can lay it back in the case without any bearings dropping. Then I can slide the counter gear

shaft into the case and counter gear. While you slide the steel shaft in, it will push out the broomstick. 



Counter gear


M22/M20,M21 counter gear



Input Shaft - 4th gear


M20 26 spline




10 spline input shaft and counter gear




26 spline input shaft and counter gear







M20 Gears 1-2-3-4

















M22 Gears 1-2-3-4



1st gear/sleeve


2nd, 3rd & 4th gears




M22 gears (missing 3rd gear)  



Plastic speedo gear





Part No. Side Cover Tag for my M20


My Muncie part no tag



This Muncie tag is a repro. Don't be taken on eBay for a used or NOS piece that's a fake. 


1970 Camaro Muncie tag #s:
3952659-RPO M20 w/RPO L34, L48, & Z28
3968011-RPO M21 w/RPO L34 & Z28
3978766-RPO M22 w/RPO L78
3968012-RPO M22 w/RPO Z28



TCS Switch Muncie Side Cover





Input Shaft bushing






Speedo cable adapter 



From my 71 Z28. My 70 Z28 is the same except it's has P5 rather than P7. See pic below.

Part # 3950352 (it has Stewart Warner and ratio .8241 stamped on it).

Used on 1970-75 all ST (standard transmissions)


From my 70 Z28


new GM oil seal part # 10054241 as of Sept 2012

19 tooth speedo gear




Speedo cable route




1970 Cross member





Shift forks



Shift forks on side cover




Worn and New Gears and Sliders


Worn M22 engagement teeth. The gear itself would take a lot of punishment to break.

Too bad the engagement teeth wear from slamming into the slider.




Worn M22 engagement teeth. The gear itself would take a lot of punishment to break.

Too bad the engagement teeth wear from slamming into the slider.


M22 new - look at the diamond engagement teeth











Counter Gear Instructions