Hello all! I will be doing a conversion on my 89 f250 with the 7.3 to 4x4! I intend to convert it because it only has 86k on it and is really clean.

I currently have a 87 f250 with the 6.9 for parts.

I grabbed a ZF off of a 1990 F450 for the "4x4" transmission, going to grab the transfer case off of the 87, since the older truck has a c6 in it. Everything looks like it will be super easy to convert it over, and I plan to post pics as I go.

Couple of questions though about the front end. I see that there is an L shaped bracket going from the K member to the frame rail, that will need to be transferred over, right?
I'm also looking at how the front shackle mounts up. The 4x has a recessed bit in it, whereas mine is completely flush. What would be an easy way to mount up the front shackle without having to do too much fab work?

Both pics are on the outer side of the passenger frame rail.


1987 F250 4x4 6.9




1989 F250 2x4 7.3

 

how you go about adding the mounting for the front axle depends entirely on which axle you are swapping.

which axle are you going to use?

 

Thanks for the reply, it's the Dana 50 IFS with leaf springs. I don't plan on doing any serious offroad with this truck, just want to get the 4x4 so I can pull a snowmobile trailer with a camper on the back and not get stuck on road with snow.

 

you aren't going to get any flak from me, on or off road, for using the ttb. they're awesome.

how much have you looked into the swap? it's straight forward, but you have some options.

i'd consider a small lift, itll help with geometry and there are better spring options when going that route.

you can do an rsk, and use an rsk mount kit, but the shackle needs to be tubed through the frame up high to get the geometry right. this is the best way to do it, but its more fab work.

 

After finally figuring out what the difference between the 44HD and the 50, I found I have the 44HD, hopefully it won't make that much of a difference. I have my old man's truck sitting right next to mine and see that I'll have to steal the shock absorber tower and rear shackle mount which should be just a bolt on after drilling the old slugs out.

Really it all looks like an easy swap, except for the front shackle mounts and boxing in the front end. Tried finding some good pictures, but they were all off of a 91 or newer which are different. Do you have a link to the adapter kit?

 

Hey all, still working on my project, pics soon to come. Still hung up, would the Reverse Shackle kit for a D60 work with the D44HD indipendant suspension? Only RSK I can find show for the D60 application.

 

Rsk does not work with ttb unless you have a decent sized lift, or the rsk kit comes with the tube for the upper shackle bushing to be through the upper part of the frame.

 

So far the kits I have found do not mount through the frame, and I did find that you cannot use an RSK with the ttb due to the way the suspension theory works. I'd rather not go with too high of a lift.
-What about welding a stack of washers to the inside of the frame and bolting the upper shackle bracket in that way?

 

Conversions are always interesting...each one is slightly different depending on ability and parts availability. I think you are going to run into a few issues dealing with the 3/4 ton TTB into the 2wd frame. I'll list out a few knows so you have some background knowledge and can better figure out which way you will go.

First: all front suspension mounting points are the same between all 80-96/97 F150-F350 2 wheel drives. That means the I-beams (TIB), radius arms, coil springs and shocks all mount the same. The rear springs and hangers are only different in the 2wd F150 (2.5" wide springs vise 3.0" wide springs).

Second: 4 wheel drive F150s (and Broncos) Twin Traction Beam (D44 TTB) use the same mounting points as the 2wd's. That means you could drop out the TIB and bolt the D44 TTB without changing anything on the frames. You can also swap radius arm mounts and TTB/TIB center pivot mounts between them all. Essentually the 4wd F150 frame is the same as the 2wd F150-F350 frames (aside from the thickness and hight on the heavier frames of course).

Third: 4wd F250 and F350 use different mounting points, not just for the leaf springs, but also the center pivot brackets. The D44HD/D50 beams are shorter in lenght than the D44 beams. The engine crossmembers are different (than the TIB/D44 TTB) with a slightly reshaped area where the center pivots mount and different bolt holes. Even the F350s with D60 use the same engine crossmember as the D44HD/D50 trucks.

So, with that information, you can see that you are faced with a few challenges bolting up the D44HD TTB to your 2wd frame...the center pivot brackets will not bolt to your engine crossmember and the TTB will not bolt into the current center pivot brackets.

I am not intimate with the D44HD beams and how they compare to the D44 beams as far as the balljoints and balljoint spacing...I do know they are different between the D44 and D50 though. If the D44HD was the same as the D44 in that aspect, I would just use D44 beams and radius arms, and then swap on the D44HD knuckles...but I believe that isn't the case.

So you are left with devising a way to get the D44HD center mounts attached in the proper location on the 2wd frame.

For the leaf springs: you would need to transfer the rear hanger, which would be fairly easy. For the front shackle mounts, I have seen some guys that remove the inner portion of the 4wd frame and transfer it to the 2wd frame. Then they slit/notch the bottom of the frame for the shackle to go through and make up the difference on the outside with a sleave or spacers.

If you want to use an off-the-shelf RSK, you would need dropped center pivot brackets, most likely 4" for a 3.5" RSK or 6" for the 5.5" RSK. OR, as already mentioned, find a low lift RSK, but you would probably still need the 2.5" drop brackets.

If I were doing it and wanted it to remain 'stock', I would just use the 4wd chassis and swap the good body and 7.3 on to it.

If I wanted a nice riding, good driving truck, I would modify some beams to mount to the stock 2wd pivots, use radius arms and coil springs. Most likely us D44 beams and find a way to make them 8 lug.

 

washers wont do it, but you can cut and weld a piece of dom through the frame, and box if needed, to get your bushing in. washers would do it if you didn't need a bushing...

ford005 raises some good points above, but anytime I've swapped a ttb into one of these trucks it's always bolted up and I never gave it any other thoughts. I honestly cant say if I've gone ttb from 2wd (I've probably done dozens of swaps on who knows what at this point) but I've definitely done dana 50 swaps on 4x4's. easiest way to determine whether you have something that works is to source an axle or a donor truck, for measurements. shouldn't be too hard considering you have a d44hd in your possession.

at any rate, it can be done...just get some solid measurements and then do what needs to be done, one thing at a time, to get 'er in there.

 

I'm almost done doing this on my truck but using a d60, for the front i got a big solid pipe plug machined down to make the offset needed for the front bushing and got it welded in


Before that i removed these from the donor frame



Then i removed the three rivets holding the rad mounts on and bolted the bracket on then driller the other 3 holes. I also used a piece of steel as a template on the old frame drilling a few holes in it to line everything up to drill the shackle hole. Then i got the thick washer welded on and cut the frame for the shackle.





For the rear hanger i had to remove the body mount to be able to drill all the holes but it's easy to do just measure from the front shackle hole back on the donor frame and repeat on yours




As for the shocks, i reused one of the coil spring bucket holes as it was pretty close, the only thing is its an inch higher but the shocks have lots of travel so no issue there.




Doing the holes for the ttb pivot brackets are going to be a challange but if you can make a template off of the donor frame it should be easy to do.

Good luck

 

I really appreciate all the input, and taking a closer look the 2wd crossmemeber is slightly different than the D44HD, looking into a D44 swap, I don't want to lose the 8 lug nor use Chevy parts to make a Frankenstein, so I'll have to give it some thought. I do however have a lead on another crew cab and a rolled F350 with a D60 in it, maybe that will be my actual swap