I have a 1980 F150 LBW regular cab that is 2wd. I have just got my hands on a rusted out 1985 bronco with good drivetrain, and plan to swap the 4wd components into my current truck. Both have a 9" rear axle, so I plan to just swap the 3rd member, rather than the entire axle assembly.
My only real question concerns the driveshaft/transfer case. The Bronco (C6 trans) uses a bolt on yoke at the TC and a double cardan front joint, with the slip/stub in the shaft. The only 133" WB F150 4x4's I have found all use a slip yoke at the transfer case, but they were all AOD trans equipped and were 85/86 models.
Did the C6 equipped 4x4 F150's use the slip yoke or bolt on yoke style transfer case? I haven't found any trucks in salvage yards with the bolt-on yoke transfer case, so that rules out getting a used driveshaft and rebuilding it.
I know I can just get the Bronco shaft retubed to the proper length, but will I need to stick with the double cardan joint, or can I simply eliminate that and use a 2 joint shaft?
I have no plans to run big tires, or a lift of any kind. I also do not plan to do any serious off road stuff. The main reasons for doing the conversion are 1) better rear gear ratio (3.50 vs current 2.75) 2) low range for backing trailers, as the C6 isn't really the best at this task, and 3) there's a few times a year that it would be handy to be able to lock in the front axle. Having got the drivetrain for free also doesn't hurt......

I know the rear spacer blocks are different between bronco and F150, but I have already gotten a pair of the truck blocks.

 

I've read in this forum before that all 80-96 Broncos used fixed yoke transfer cases and all 80-96 F-series used slip yoke cases, and I've never heard or seen anything to the contrary of that.

 

So does this mean that using a Bronco transfer case in an F150 is a bad idea? I always thought the bolt on yoke design was better than the slip yoke.
I realise that using this case will likely result in having to get a shaft custom made, but that is about all the actual cost of doing the swap will be. Other than rear shocks and brake hose, which are due for replacement anyways.....

 

It just comes down to what you want, but you'll need a driveshaft either way. Might as well get what you want-

 

That's pretty much how I viewed it.
No one has yet touched the question about the double cardan joint. Keep it, or delete it?

I figure the bronco never really saw much off road use, as it still has the auto front hubs. This should translate to the front drive and transfer case being in pretty good condition. It was running when it was parked, and that was due to fear that the body would keep going straight when the chassis turned........