1978 F-250 conversion to 4 wheel drive

cszeman · #1 (**permalink**) 02-13-2008, 01:43 PM

Hi all,
I have a 78 F-250 supercab camper special 4x2 with a 460 (with I think a c6 tranny?) with only 57,000 original miles on it (passed down to me from the original owner=my dad). I would like to convert it to 4x4. I was hoping to just swap the drivetrain but after talking to local autowreckers, they said it would be much easier to find another 4x4 supercab truck from the same generation and just swap the body/chasis (Apparently frame on a 4x2 different than the frame on a 4x4??). What do you all think? It's not very easy to find a 4x4 supercab f-250/350 that I can part out or to do the swap of the body/chasis with. However there are a few 4x4 pick-ups available. Is it even possible to utilize the drivetrain from the pick-ups onto the supercabs? I realize that if anything the rear driveshaft would need to be extended (or can I make use of the rear driveshaft currently on my truck?). Would the tranny/transfer case that bolts up to a 400 or a 351M bolt up to a 460??

Mil1ion · #2 (**permalink**) 02-13-2008, 01:47 PM

IMO, If you want a 4x4 ...then buy a 4x4

If you must swap or retro fit something...... make it the cab and box onto the 4x4 chassis

codyingersoll123 · #3 (**permalink**) 02-13-2008, 01:53 PM

yes...460's came with c-6 auto tranny's...and yes the tranny/t-case combo from a "M" family motor WILL bolt directly to the back of your 460. Your 2wd driveshaft will NOT work after you swap tranny's and t-cases...as it will be to long. You need to find a tranny, t-case out of a big block "FE" or "M" motor,front axle out of any similar year and front and rear drive shafts out of a supercab. It would be much much easier if you found a donor big block supercab truck and just stripped everything you need off that....

oh and also make sure your front and rear axles have the same gearing in them....so you might want the back axle too...depends on what you find...

FordTrucksKickGM · #4 (**permalink**) 02-13-2008, 02:49 PM

The easiest thing to do is find a SuperCab 4x4 frame and swap bodys and motor. Be patient. They are out there. You could swap the 4x4 parts from a donor truck on to yours but there would be some custom fabricating. The other option might be to get a regular cab 4x4 frame and lengthen it.

tatonka04 · #5 (**permalink**) 02-13-2008, 03:01 PM

You might even try putting a request in the wanted section of the 73-79 classifieds for a 4x4 supercab frame. There was 2 on there a few days ago that I don't think sold. Sometimes you have pretty good luck. Just my 2 cents?

cszeman · #6 (**permalink**) 02-13-2008, 11:04 PM

What type of custom fabricating would be required? Are the 4x2 frames different than the 4x4 frames?

75F350 · #7 (**permalink**) 02-14-2008, 03:51 AM

2wd frames are fairly different, but should not be ruled out. Much has to do with how much lift one will consider, and exactly what tpye of suspension will be used. With enough lift, the factory 2wd x-member can still be used, and a link (or radius arm) suspension is easy to fit. Even a 2wd transmission can be used. This is easily solved by using a divorced t-case.
You do not need a donor truck, this is not much different than a SAS for a later model TTB truck. Some cutting, and some welding is required, and of course tha ability to read a tape measure is a must, but by paying a little attention to detail, it can be pulled off fairly easily.

teds74ford · #8 (**permalink**) 02-14-2008, 08:27 AM

Not to pop your balloon, but if you have this many questions, you should hold off for a while. I would say to convert the existing truck, but AFTER you read up alot on suspensions, welding, steering geometry, etc. I decided to do a 4x4 conversion, and I was way over my head. Now, it wouldn't be a problem, but back then it was a headache.

Your simplest would be to score a disc brake dana 44, divorced t-case, and put in leaf springs. It will have to sit quite a bit higher than stock because of the front crossmember, but it can be done. While you are at it, you should consider doing crossover steering. You can use chevy TREs and COULD use your existing steering box. It is really tall, but depending on how high the truck it, it could work.

Again, read up for a while before you commit. Good luck, and welcome to FTE

tatonka04 · #9 (**permalink**) 02-14-2008, 08:45 AM

Hey Teds74, you beat me to it, I was just getting ready to recommend you because of the good job you did on yours. Nevermind. But Cszeman, do check out his gallery pics, it might help and give you some ideas.

teds74ford · #10 (**permalink**) 02-14-2008, 01:34 PM

Thanks, man.

One thing I tried to do was use as many factory parts as possible. I don't think I would do that again. For the price, you could probably buy 4 link stuff from one of the offroad fab places, the cheapest front axle you can find, and a divorced t-case. Oh well. Maybe next time...

cszeman · #11 (**permalink**) 02-15-2008, 05:18 AM

Thanks for the replies guys!

teds74ford · #12 (**permalink**) 02-15-2008, 08:57 AM

No problem. If you have any specific questions, feel free to PM me. I will try to help.

crazyredneckanyhow · #13 (**permalink**) 02-15-2008, 12:22 PM

Yeah im in the planning of a 4wd conversion on a 79 crewcab. Ive finally decided on coils and longarms (4 to 5 ft radius arm) up front. Im a welded and fab guy by trade so its not gonna be as hard on me as the average joe. But i will say ive been planning for id say 2 yrs? Sounds bout right Ed? 75F350 has alot of good info to provide and Ted has done it. Listen to these guys and ill chime iin where i can. Front axle bracket drawing is at the machinist now so i may get started soon.