I'm thinking about swapping my np 435 4 speed tranny for a ford ZF 5 or maybe 6 speed tranny. I know that the ZF was use on 460 and 7.3 Desiles. And a 400M has a big block bell housing bolt pattern. Has any one done this. Does any one have any ideas. I drive 42 miles to work and 42 mile frome work every day in my 79 f150 and I love the truck but the fuel cost is starting to get old. I would like the overdrive of the ZF.
Thanks

I'm thinking about swapping my np 435 4 speed tranny for a ford ZF 5 or maybe 6 speed tranny.  I know that the ZF was use on 460 and 7.3 Desiles.  And a 400M has a big block bell housing bolt pattern.  Has any one done this.  Does any one have any ideas.  I drive 42 miles to work and 42 mile frome work every day in my 79 f150 and I love the truck but the fuel cost is starting to get old.  I would like the overdrive of the ZF. 
Thanks

[FONT=Times][SIZE=7][COLOR=blue] I too am trying to install something similar to your project but have not gotten alot of support from anybody, most people tell me just to put in an automatic. My truck has a 3 spd. with a clunky floor shift conversion that is horrible. I will let you know if I hear anything, please try to return the favor, sorry I couldn't help out but, figured I would let you know that you aren't alone...

I'm thinking about swapping my np 435 4 speed tranny for a ford ZF 5 or maybe 6 speed tranny.  I know that the ZF was use on 460 and 7.3 Desiles.  And a 400M has a big block bell housing bolt pattern.  Has any one done this.  Does any one have any ideas.  I drive 42 miles to work and 42 mile frome work every day in my 79 f150 and I love the truck but the fuel cost is starting to get old.  I would like the overdrive of the ZF. 
Thanks

Great minds think alike! I have a 78 F150 with the same drivetrain and have been researching the same conversion. From what I understand, the zf should bolt right up to the np205 t-case. The zf case is longer than the 435 by possibly a couple of inches so driveshaft lengths will need to be changed.(This of course relates to 4x4, I don't know how much difference for a 2wd) The zf bellhousing is part of the transmission housing so it will probably be necessary to convert to a hydraulic clutch linkage as in the newer trucks. I don't know yet if the flywheel diameters are the same to be sure the starter motor matches up, but I imagine it does.
I haven't done this yet myself, but I hope to start gathering up parts this summer. I'm dissappointed no one has covered this before in the magazines, but I guess if there are no adapters needed there is no money to be made. I hope this helps, any further input or even corrections would be appreciated.

I belong to two other forums related to Ford products at least one of them should have info on what the three of you are trying to do with your transmissions. They are
www.ford-trucks.com and fordsix.com. Hope that helps.