Muncie M21 trans question
Thread Starter
Burning Brakes
Joined: Aug 2001
Posts: 1,002
Likes: 0
From: Bay City MI.
Muncie M21 trans question
Is it possible to switch the guts of my Muncie m21 close ratio trans for the M-22 rock crusher style? If so where could I find the parts to do it, have heard the M-22 is hard to find. Thanks!
Race Director
Joined: Aug 1999
Posts: 18,126
Likes: 174
From: WI
Re: Muncie M21 trans question (LT1-Tom)
Tom,
Not that i would of traded,But i just sold a M-22 for $1900 so be prepared. You can try this guy he will (probably) give you some credit for your M-21 gear set (if it is good) he has ALL the parts you want, good used stuff and NOS GM. STAY away from the off shore (made in Spain or Italy) M-22 gears they are NOT i repete NOT the same as the GM stuff. Call Eric after 7pm central at 262 942 8882 ...redvetracr
Not that i would of traded,But i just sold a M-22 for $1900 so be prepared. You can try this guy he will (probably) give you some credit for your M-21 gear set (if it is good) he has ALL the parts you want, good used stuff and NOS GM. STAY away from the off shore (made in Spain or Italy) M-22 gears they are NOT i repete NOT the same as the GM stuff. Call Eric after 7pm central at 262 942 8882 ...redvetracr
Melting Slicks
Joined: Jun 2001
Posts: 2,429
Likes: 14
From: CA
Re: Muncie M21 trans question (LT1-Tom)
If you have no luck with the guy redvetracr recomends, here is a list of old GM part numbers for the conversion:
Reverse gear p/n 3879997,
First gear p/n 3924796 (non-needle brg),
Second gear p/n 3879999,
Third gear p/n 3880845,
Cluster gear p/n 3905466;
and either a 26-spline main shaft 3978761, or a 10 spline older version 3925691.
Pre-1966 muncies must be bored out to accept the larger 1" countershaft 357233.
Factory over-the-counter racing M22 upgrade parts:
Slotted synchronizer blocker ring 344243, -helps with oil control for faster shifts.
Longer high-load 20lb side detent spring 3831718,
Special synchro assy 344241 - prevents 1st gear hopout,
Special synchro assy 357239 - helps trans stay in 3rd when letting off throttle,
Special first gear needle bearing roller unit - (gear-3965752, sleeve-326578, needle brg-9433516,
& washer-326579)
Good luck on finding this stuff. :seeya
[Modified by 71coupe, 10:29 PM 10/30/2001]
Reverse gear p/n 3879997,
First gear p/n 3924796 (non-needle brg),
Second gear p/n 3879999,
Third gear p/n 3880845,
Cluster gear p/n 3905466;
and either a 26-spline main shaft 3978761, or a 10 spline older version 3925691.
Pre-1966 muncies must be bored out to accept the larger 1" countershaft 357233.
Factory over-the-counter racing M22 upgrade parts:
Slotted synchronizer blocker ring 344243, -helps with oil control for faster shifts.
Longer high-load 20lb side detent spring 3831718,
Special synchro assy 344241 - prevents 1st gear hopout,
Special synchro assy 357239 - helps trans stay in 3rd when letting off throttle,
Special first gear needle bearing roller unit - (gear-3965752, sleeve-326578, needle brg-9433516,
& washer-326579)
Good luck on finding this stuff. :seeya
[Modified by 71coupe, 10:29 PM 10/30/2001]
Le Mans Master
Joined: Sep 2000
Posts: 5,635
Likes: 4
From: Orlando Floriduh
Re: Muncie M21 trans question (LT1-Tom)
Try http://www.fivespeeds.com. Find Muncie 4 spds. There is a Mucie forum that you can post your questions .
Safety Car
Joined: Dec 1999
Posts: 4,148
Likes: 5
From: Roxbury NJ
Re: Muncie M21 trans question (redvetracr)
redvetracr, I priced a few new parts for my muncie recently. Specifically, and input shaft and cluster gear to convert my M21 to an M20. Are these parts available from GM, or are all the new parts cheap imports? I never though to ask that.
-Joe
-Joe
