Does anyone know the diffrence between a 78-79 1/2 ton 4X4 steering gear and a 78-79 3/4 ton 4X4 steering gear?
I have a 76 3/4 ton I wish to convert to power steering and I know where I can get a 78 1/2 ton gear but I havent had much luck finding a power 3/4 ton gear.
Thanks in advance Leadmic

 

On my 77 f250 4x4 I used a 78 f150 2 wheel drive power steering gear. I was told that a 4x2 or 4x4, 150, 250 and so on would all work. Although there was a bit of fabricating, boxing in the frame, new drag link and shortend steering shaft. Also the pitman arm off a my donor truck was angled up a bit so I flated it so that there would be less of a angle for the drag link to over come. Just watch out that you don't warp the hole for the drag link. I works way better that the old control valve, power system did. Any questions just post them.

mike

 

Hey Mike thanks for the imput I just have a few questions.
1# Did you mount the gear on the inside of the frame if so does the gear and pitman interfear with the leaf springs at all?
2# What did you use for the drag link that connects the pitman arm to the steering arm?
3# What did you use to box the frame?
4# How did you shorten the steering imput shaft?
Thanks for your help Leadmic

 

[updated:LAST EDITED ON 29-Apr-02 AT 10:58 PM (EST)]I mounted the gear on the inside of the frame, right where the old box was. I used 5/16" plate. From the crossmember under the front of the engine i went 8" long and cut to fit, so that it was flush, not over-lapping with the top of the frame. Make sure you put a weld a couple of 1/2" studs or anything like that behind the plate before you weld it to the frame. that just helps in stoping the plate from bending. But try to avoid the general location of where your new box is going to bolt. Then tack the plate in place. Now hold up your new steering box and mark the holes and drill them out. At the bottom of the frame, i had to grind in order for the box to fit flush to the frame. Once you mark the holes on the plate there should be one thats above the frame. For this all you have to do is weld and 1/2" thick tab long enough and high enough for the last hole to bolt to. If you really want to be sure of the plate you can always put a couple of bushings around the bolts in between the frame and plate.

As for the pitman arm interfearing with the leafs, i didn't have a problem. The front of the leafs move very little anyways.

For the drag link i used two tie rod ends with a 7/8" treads. Then i bored out a 1 1/4" x 5" piece of round stock to 13/16", and threaded that. The only problem with one of the tie rod ends was that it was a left hand thread. I just re-threaded it to right hand threads. Then just centre your wheels dead centre from lock to lock and take you measurements for your drag link. 1/2" less is what i went with. This gave me some adjustments. Remember that the tie rod ends will be inside the bored out sleeve when measuring.


As for the steering shaft, you can A take it out or B leave it in.
If you leave it in, when the steering box is in take a measurement from the box to the end of the steering column. I went with 1/2" less to compensate for play. Then just cut out the extra bit from the middle of the shaft. Chamfer the ends on each side of the shaft. With a piece of angle iron underneath of the two ends clamp them down, true as possible. then just weld away. hope this helps.

mike

 

leadmic , The draglink for a 77 , 78 , & 79 f250 4x4 is the same one as shown in the current LMC catalogue on page 92--I don't know if it will fit a 76 or not or if your truck is a 4x4----but you might take a look!!!!!And , a question for mtford , I restored the the old power assist steering system on my 77 f250 4x4 and it has just proven to be a real disappointment to say the least so I am going to convert my trk over to the regular psteering system----I'm wondering how long did it take you to make the conversion and what was the most difficult part----I think for me it would be getting the steering box "set" in the correct position so it moves the front wheels thru a full range of motion---Any comments or suggestions----and did you happen to take any picture's of your handiwork , thanks for any and alll help , fd

 

All together it took me a good weekend to do. The conversion took me a complete day to do. When i did it I took off the grille , rad, bumper, all the old steering parts, fan, and the power steering pump. Although you could just lift off the front clip. I forgot to add this earlier but taking out the rad is very important. Since the new "Integral Power Steering Gear" is longer and taller than the stock box, the rad suport has to be notched in order to fit. The bottom side of the rad has to be ground to fit too. For setting up the box, the bottom of the the gear housing is 1/8" up from the bottom of the frame, and the whole unit is perpendicular to the frame.

As long as the box is perpendicular to the frame, the plate is flush with the top of the frame ( the bottom wont be due to the bend at the top of the frame. it will be in roughly 1/2" or so) and the rad and support are ground it should fit and work fine. I should have pics soon, I just have to develope my film.

Heres what parts i used on my truck:

-Intergral PowerSt. gear,
# D9AC
3580-A2

- 6" long pitman arm (bent so its flat)

- and a 14 13/16" drag link (from centre to centre)

Well hope this help, and good luck with your project.

mike

 

Thanks mtford1!!!I have been trying to gather up as much info as possible on this subject before starting so as to define my various choices and i think that I pretty much know what I'll have to do.....So if you deveolp your film send me the pic's via email if you get the chance , thanks for your response , fd :-X11

 

 

Thanks for everyones help but my question was only particaly answered. The part that was not answered was does anyone know the diffrence (outside of the pitman arm) between a 78-79 1/2 ton P/S gear VS. a 78-79 3/4 ton steering gear? If their is no diffrence please let me know and if their is a diffrence could someone please tell me what they are?
Once agin thanks to everyone for their help the info from this board is the best. Leadmic