Posted by Vaughn [172.69.33.239] on Thursday, December 29, 2022 at 12:32:43 :
In Reply to: Re: M37 Differences - Correction posted by Greg Coffin [172.68.35.50] on Thursday, December 29, 2022 at 10:54:33 :
The PIF has a comparison between the two M37 transmissions and the civilian NP420. Parts in red font are shared between the M37 NP420 and the civilian NP420, parts in black font are shared between all three transmissions, so not all internal parts are NP420 in the earlier synchronized transmission.
The shift towers or transmission covers between the early M37 and NP420 are in the same location for the shifter, but the the gear forks will not interchange. You can install an earlier cover on the NP420, but you have to change forks to the NP420 forks. Marcel and I ran into this issue when we worked on his 53 M37. Someone had installed an NP420 and used the earlier shift tower which caused some confusion when we order a new tower from John and MWM.
The one thing I liked about the earlier tower is that it uses set screws to lock the forks instead of pins which makes it a little easier to work on.