Posted by CSCameron [108.162.215.97] on Wednesday, February 17, 2016 at 18:00:29 :
I finally got the M37 NP420 Transmission swapped into my 55 FFPW. Turns out that the front bearing cover on the M37 NP420 has a larger diameter than the one on my 55. That is why it would not seat all the way to the bell housing. The m37 NP420's cover is roughly 5.1" in diameter and the "after type" cover is 4.75". However, everything else is identical with the cover except the larger flange.
So, I just swapped out the covers and reinstalled, no problems. I had the tranny aligned all the time. The hole in the bell housing was just too small for the m37 cover to fit into.
Just thought I'd pass this along as I had always been told (and read in the archives) that this swap was a direct bolt in. The bolt holes for the tranny do line up perfectly with the bell housing pattern but that cover was a head scratch-er.
CLark
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