After several months of searching for a cheap F250 4x4 junker, I finally found one. And boy, is it a junker! But it has the parts I want: HP dana 44 front axle with discs, C6, NP205 t-case, power steering and a 460. I plan to take all those parts and put them in my '71 F250 4x4. But first I have some questions.

I bought this as a '78, but I am not sure it isn't a 77 1/2. The VIN is X26SKAE6428. It has the '78-'79 grill, but the round headlights. I thought they all had square headlights, so that's why maybe I thought it could be 77 1/2. Not sure if 77 1/2 had round lights or if some '78s had rounds??? Anyway, it has the HP diff, which is what I wanted. My question is regarding the swap. I always thought the frames got wider, post Highboy in 77 1/2. Is that just in the back? It appears that the spring perches will swap right over to the '71 without moving them. I always understood that I would have to move them inboard a bit. Can someone clarify that for me?

Last question, regarding the power steering box. I have read several write ups on the conversions and all of them that I recall called for cutting into the '71 frame to make it match up with the '71 running gear. If I am using the '78 axle, do I need to worry about that? The linkage seems to be very similar as far as location and angles goes, but that's just eye-balling it. If the frame is the same width, then I assume I can just mount the '78 box on the '71 frame in the right locaction (some distance further forward than the factory '71 manual box).

Thanks for any advice you can provide. I'm getting fired up for this (mostly the power steering upgrade)!

 

About the headlights - the round lights are present in the 77 1/2 and I believe early production 78's.

 

Comet, is your t-case mounted directly to the back of the transmission or is it seperated by a driveshaft (divorce mounted)? Grills can be changed, etc. etc. but one of the easiest ways to tell if your truck is '77 1/2 or earlier is the location of the t-case.

About the frame widths...
There's always an exception to every rule. That damned Murphy and his stupid laws. (: Best thing to do is measure both frames and then you'll know for certain. You're right, though...'78-79 F-250 frames were wider. Still, it's a relatively easy, albeit time consuming, swap.

 

Buddy, it is a married T-case. There is an adapter between the tranny and the t-case, not a driveshaft. So, what does that tell me? I know my '71 is divorced. I have a spare C6 sitting around that came from a '75 F250 4x4 I could use if that doesn't work (except I'll need to figure out what to do with the input side of the t-case).
Thanks for the info. everyone.

 

Well, it means that your new (old) truck is not an early '77 as you suspected and that the frame widths will differ between that one and your '71.

 

Ahhh, gotcha. So it is in fact a '78. Actually I suspected a 77 1/2 or early '78. So they went to a married t-case starting in 77 1/2. I assume I can still use it on the '71, I just have to move the cross member up a bit and narrow it up or fab something, correct?

 

Pretty much.

 

Why not just put the 71 body on the 77 frame? you'll just have to move the bed bolts out. The wheel base is the same.

 

According to my dealer brochure, for 1978 the grill changed on all versions of the truck and for base model/Custom trim level, the headlights were round. The XLT came with the rectangular lights.

Then in 1979, all the models came with rectangular headlights.

 

It's a 78 plus, it was assembled August 77

It is also a *Custom* trimline.

Rectangular not Square headlights are found on 78's with Ranger trim & higher.
This includes Ranger Explorers,Xlt's & Lariats

 

as for thye steerimg conversion i know of a guy who provides you with th custom brackets as well as all new steering components for $850 his name is brent conversions AT VERIZON dot NET

 

Mil1ion,
I think that rectangular headlights were implied. It's a common reference.

joepickett,
$850 for the steering brackets???? Holy smokes that's steep! Did you know you can (God forbid I mention this) fab in a GM box and it'll work great with next to no effort. You can also fab in nearly any Ford box depending if you're going with crossover steering and how you mount the steering arm to the diff. It's really not neccessary to spend that kind of money and not that hard to do. Please don't tell me your considering buying that conversion. I'll help you if you need with diagrams, etc.

 

Thanks for the great info.
Mark A., the '78 is a Super Cab, that's why I wont use that frame.
Joepickett, I don't need a conversion kit because the '78 has PS that I will be using. Every PS conversion write up I've read I feel like I can fab anything I need to make it fit.