Posted by Vaughn [172.68.35.114] on Monday, March 10, 2025 at 16:24:16 :
In Reply to: NP 420 Transmission for my 46 WDX posted by Kent Croskey [172.69.59.70] on Monday, March 10, 2025 at 13:34:53 :
Welcome! There are a couple ways you can go in upgrading to a synchro mesh transmission:
An early NP210 or the later NP420 Dodge M37 Military Truck transmission will bolt to your current bellhousing and also requires the late 56 cab floor trans cover and P-brake/TC lever trans mount.
A late 56 and later FFPW NP420 will require the bellhousing swap to the FFPW Civilian bellhousing for the civilian NP420 and also the cab floor trans cover and P-brake/TC lever trans mount.
The PIF at the top of the forum, first page has WC/FFPW salvage dealers that can assist with the parts should someone on the forum not have what you need.
Also Rick Tudor at the link has parts as well.
There is a post below you might want to look at on the trans swap.