Muncie Transmission Swap
 

I have a 65 GMC shortbox with a 3 on the tree and I am interested in putting in a Muncie 4 spd. Has anybody done this before? Could you let me know how it went with the clutch linkage and the crossmember etc.? Also what is the best model (M20, M21, or M22) to go with mated up to a 400 smallblock and a 3:73 12 bolt rearend? Thanks

I'm not real familiar with this combination firsthand,but a friend did the swap on his '64 Chevy. He had to get a special shifter to clear the seat (he said-I suspect he just wanted a Hurst shifter instead of the factory type).The clutch linkage is fine as is. Depending on how you drive and if you have the bellhousing rear engine mounts,you might not even need a crossmember for the transmission. It's possible your 3 speed already has a mount under it;if thats so,you might need to unbolt the crossmember from the frame and slide it back enough for the mount to match up to the 4 speed,then re-drill the mounting holes in the frame.I guess thats about all the rough spots. Everything else should be easy. I always wanted to try hooking a 4 speed up to the column linkage and run reverse off a separate lever or a cable.

Speed,

You could always go with the SM420 -- Granny first 4 speed that was optional in your truck. That would be a pretty easy swap.

Brian

The Muncie 4spds will bolt right in place of the 3spds.

Just read last night in one of Hemming's magazines that the M21 is a direct replacement for the 3spd manual or TH350. Same length and same spline count output so no driveshaft changes required. No first hand info though.

drive shafts is gonna be to long
 

65 3 spd was unsincro 1 st gear this made the trans shorter then the turbo 350 auto the m21 with a bell housing is a dirrect swap with the auto, not the 3spd you can use a mid 50s comp plus shifter and shorten the drive shaft youll be fine, also if the trans is from a camero the spdo drive ion the passenger side and you cable wont reach.
Ed

Thanks for all the info everybody. Now that I found all of that out, I'm also considering a Super T-10. any thoughts?