Author Topic: Muncie Transmission Help!  (Read 3168 times)

coachnelson4

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Muncie Transmission Help!
« on: December 08, 2008, 05:09:16 PM »
I bought a muncie from Turkey Rod run last weekend and need some help.  The main case is from a '63-'65 vehicle which I believe is a chevelle since it has a K on the top for the vin but I've read they don't come with a date code to let me know if it is a M20 or M21.  The front shaft and tail shaft is from a '68-69 camaro.  How can I tell if it is a M20 or M21 and what is the best rebuild kit you guys have seen for the Muncies? 

JohnZ

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Re: Muncie Transmission Help!
« Reply #1 on: December 08, 2008, 05:17:26 PM »
Put it in first gear and see how many turns of the input shaft it takes to produce one full turn of the output shaft; if it takes 2-1/4 turns, it's an M21 (2.20 1st gear) - if it takes 2-1/2 turns, it's an M20 (2.54 1st gear).
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coachnelson4

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Re: Muncie Transmission Help!
« Reply #2 on: December 08, 2008, 05:25:32 PM »
Thanks for the reply.  I'll have to try that when I get home.  Any recommendation on a rebuild kit or rebuild manual / video.  Thanks guys!

Dusk Blue Z

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Re: Muncie Transmission Help!
« Reply #3 on: December 08, 2008, 11:42:19 PM »
I am pretty sure these guy's are the source that other vendors get their parts from. I know they cast the super case...

http://www.autogear.net/index.htm

Mike

1968RSZ28

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Re: Muncie Transmission Help!
« Reply #4 on: December 09, 2008, 12:04:51 AM »
Any recommendation on a rebuild kit or rebuild manual / video.

As for a manual, the factory Chevrolet Chassis Overhaul Manual has step by step overhaul instructions and great diagrams.  Have fun!     :)

Paul

Jerry@CHP

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Re: Muncie Transmission Help!
« Reply #5 on: December 09, 2008, 02:47:02 AM »
Normally the M21 will have one groove on the input shaft, the M20 has two grooves.  However, many of the early transmissions do not have the ID grooves.  Something to check for.  There is also the small and large sycnro hubs and blocking rings issues.  You'll need to know what you have.  The early small design are junk, small blocking rings that always break or crack.  If you have the small hubs and sliders, you'll need to upgrade to the large style.  A must!

Don't buy any parts kits.  They are usually thrown togehter with cheap parts from Mexico and what ever,  I buy all of our Muncie rebuild parts out of Detroit and NY.  it's best to buy the parts seperately.  Make sure you ask questions and who the manufacturer is.  We rebuild and restore 5-6 Muncies a month at CHP, probably more than most shops do today.

Jerry

coachnelson4

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Re: Muncie Transmission Help!
« Reply #6 on: December 09, 2008, 02:51:39 AM »
How much do y'all charge to rebuild a transmission?

Jerry@CHP

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Re: Muncie Transmission Help!
« Reply #7 on: December 09, 2008, 03:47:31 AM »
Low end is $450 and the high end is $750, just depends on what is bad and what needs to be updated and or replaced,

Jerry