James

While I have the motor out of my car I was going to have the transmission rebuilt. Last year I noticed it would sometimes pop out of first or second when down shifting and using the motor to slow the car down. I was just curious to know who guys recommend to purchase a rebuild kit through for a M21? Also is it possible to rebuild the tranny myself? Does anyone carry a video on how to do it?

71SoCal

Yes, I just rebuilt my Muncie M-20 about 6 months ago.

I've got a post on it somewhere. I bought the rebuild kit and the video from 5speeds.com. It was very straightforward. The only catch is that second and third gears and the speedo gear are pressed on.

I ended up buying a press from Harbor Freight for $120. After that, I just followed the video. Also, the owner at 5speeds.com (can't remember his name) took my calls with a couple of questions.

Good luck...

James

71CoCal thanks for the information!!! Looks like I need to order a CD and rebuild kit!! Thanks.

Lostlake

I'm going through the same thing right now. I'm upgrading my engine so would like to upgrade to a stronger tranny. I talked to Tom at T&B trasmissions. He said that The M22 would be best because it has a 1" countershaft in lieu of a 7/8" in the M20-21. The gears are also thicker. The M20 cannot be upgraded to a M22 without getting a hole new transmission. He told me to talk to Bob at 4 gear transmissions, 1 630 879-8777. He rebuilds transmissions.

I'm curious as to how many H.P. your engine is and if you M20 was holding up to the horses? It's either leave my existing transmission in and subject it to 600+ HP or upgrade.

I've got a 72 and it looks a lot yours. Nice.

Thanks

ND

James

The M21 that I have in my car had never been touched other than seals and gaskets. I have 509 cubic inch motor in the car that made over 550 HP that I ran in front of the tranny for 5 years. Last year is when it started popping out of first and second on down shifts. I only run steet tires and don't rag on it all the time.