Hi and thanks to everyone on this site. I have learned a lot! I'm converting my 77 highboy to power steering from the power-assist using a 1979 f150 4x4 power steering box off my parts truck. (Well hopfully) What can I expected to run into on this and will I have to fabricate anything to make it work? I would like to do it using factory ford parts so when something has to be replaced its not a pain. Everything but the pump is leaking after sitting since 03 and now that I'm just about done with her except paint I've got down to fix or replace the power steering. I'm not running big tires just 235/85/16 on dually steel rims since it was converted to a dually years ago and that's how I remember it growing up when it was dads. I'm not doing a lot of mudding or beating on it just hauling some wood and hay and taking my little girls to schools since my six year old loves daddy's big loud truck almost as much as he does. Dad was going to haul this truck off for scrap but I traded him a running driving Chevy for it so he would have something to drive. Its a piece off my childhood I can't let go of so if you guys know anything about doing this with a 4x4 f150 box any advice would be great

 

Also what is different about the f150 steering box vs the f250/350 boxes beside one is more durable and will take more abuse. Do the have the same pitman arm and are they the same height? I know one is larger but do you think the f150 box will hold up in this set up. It seem to be tight with no play so I know its good.

 

does your f150 mount on the outside of your hb frame,,,like a saginaw.The 250 would require mods on internal frame mount,not difficult but there is some cutting and welding.

 

a popular choice for this type of conversion is a 78/79 f250 steering gear box. this box is made for 3/4 and 1 ton trucks. your putting a steering gear in thats designed for a 1/2 ton truck. i'm no professional on this but your f150 steering gear might not hold up . i'm also pretty sure that the pitman arms ARE NOT interchangeable due to the size of the shaft on the steering gear.

 

The highboy mounts to the inside and the 150 the out. What will have to be cut? When I was looking at the two it looked simple. But looks are deceiving.

 

from what I can tell I'll have to cut the inner fender to clear the steering shaft and I was going to make a brace for the inside of the frame to keep it from twisting.

 

did you try to do a search using the search box? also head over to the steering and suspension forum you might get lucky there as well.

 

Yep. Googled and binged it too. Everyone is using a 2wd f250 or a Saginaw and a few are using the 78/79 250 but no 150. If it wasn't free I'd do away with the 150 box and shoot for a 250 but cash is a little tight right now.(trying to buy a house) I'll check steering and suspension

 

Yeah I found out the shaft is longer the hard way. My cab is off a 2wd and the original column and shaft were wore out from years of no power steering. I just shortened it to fit and welded it back together (miller 350). I would love to do the 250 4x4 box but as I said I'm a little tight right now. I need take the truck for pipes and then to the farm to rework the bed and paint it. I'm not saying the 150 box would be permanent unless it works great. I just won't to know if it would hard up long enough (maybe a year) without breaking. What I was thinking is I've had a couple 79 150 4x4s and one had 38x12.5 and it seemed to handle it fine. That's way I was wondering if it would work in my set up. Thanks for everyone's input. I'm starting to think I should pull some more overtime and buy a 79 250 box unless someone has done this with good results.

 

78/79 gear box

 

everything is plated,cross member notch as well.When I did the front 3x5x3/8 cross member,I used the notch removed for spring hanger for the plating of steering cross member.I let the plate that sandwiches in the frame run all the way to the back of cross member notch,that was 3/8

 

I have a leaking '79 PS gearbox in the garage, and a rebuilt '79 gearbox in the truck. I have been contemplating a Red Head. Maybe we can work a deal that when i send the leaking one out to get the redhead, i can sell you the rebuilt i have.

 

Nice work! Thanks for the pics. It makes things easier when I go to do this if I use a 250 box. I have saved them just in case I do. I really wasn't wanting to cut anything or do alot of mods because of the engine already being in and set up to run. But it looks as if I may have to. There's an old guy up in elk creek (where I'm from) that has a salvage yard with all old trucks and cars. Mostly dodge stuff but he always used fords to drag them home so I'll see what he has this evening. Would any mid to late 80s 3/4 boxes work? I know he's got two of those

 

I thought only f250 and f350s could be high boys? I have a 78 f150 and need to change the steering box, is there a bolt on f250 or f350 box that will work? I'm willing to modify the mounts also.....
Thank you

 

As far as I know 67 though early 77 f250 4x4 were highboys. I never thought mine was until I did the cab off. Frame rails are closer together and they have the manual assist steering. I believe that's right anyway.