55.2-59 4x4 conversion with manual steering

[burnin oil]

Has anyone done a 4x4 swap while keeping the factory steering box? I actually enjoy the manual steering. Just curious of the feasibility since the factory box has forward/backward geometry or if I am stuck with doing a steering upgrade.

They reason I ask is that I broke my trans and it is decision time for me. Locate a good sm420, swap in a ch465, or swap in a 465/205 combo that I have stashed away. The truck is a dump bed so I need to keep the PTO option.

[sack54]

If using Napco 4x4 parts you do not need to change steering box.

[burnin oil]

It won't be Napco parts but either a 73+ 8 lug or a Ford super duty dana 60. I have not seen a Napco around here in years.

[vintovka]

Arms of steel may be a required. I could not drive 54 body on a the K10 chassis without it.

[mr48chev]

Fabbing a steering arm that will bolt to the left spindle is going to be the big challenge.

You can gain some mechanical leverage by going to a big truck = 4000 series and maybe larger steering box. More turns but a bit easier steering especially in a lighter truck.

This is the 57 pfd and if you scroll way way down the page past the engine specs you can find the steering box specs https://www.gmheritagecenter.com/doc...olet-Truck.pdf you would have to run the pitman arm for the box an may want to run the drag link that came with the box and build the steering arm to fit that.

[vintovka]

Big steering wheel helps too.

[burnin oil]

Ok. Thanks guy. I have a line on an 88 k20 8 lug axle. I was at the local junkyard yesterday and found a 58 or 59 GMC 370, non COE, that I plan to grab the trans and steering box out of. It's at the very back of a country junkyard and way to wet to get back there to winch it out currently. Manual steering isn't that bad. The truck is a 1 ton and I can turn it lock to lock sitting still while sitting on 265/75r16 tires. I know it will be worse with bigger tires but the will not get much larger since she is a dually. The truck will stay on leaf springs.

[mr48chev]

That steering box may not have the right steering shaft angle from the box to the wheel to fit a regular cab truck.

[burnin oil]

Very true and that has me a little worried. Supposedly the non cab forward trucks used the same tin as a pickup so I am guessing that it's close. It's hard to tell since it's laying on it's lid. The price is right so I am gonna grab it and a 5spd non OD out of a bus. I may just clip it and bring all parts forward home. Seems like alot of salvageable sheet metal. All parts are questionable. Fingers crossed. I struck a deal on the front axle last night so if all goes well that will be here next week. This little project is snow balling quickly.

[burnin oil]

Slight update. Went to the bone yard today and picked up the sm420 and steering box from that GMC 370 today. We decided to pull the 57 home tomorrow and drop the trans out. The bell housing housing in the truck will dictate the road to follow since we have 30 irons in the fire. If the bell housing is a small hole we will go back with the 420 trans, but if its a big hole I have a 465/205 ready to go. The goal is speedy repair then do the 4x4 conversion as time dictates. I have the correct bell housing in a parts truck but that means pulling the drivetrain. Shifting transmissions requires reworking the dump bed PTO assembly. I do have a lead on a 8 lug 73+ front axle tomorrow to call back on and it should be a done deal. This truck is a runner so being down is an issue. I need to keep her productive while doing other projects. Other circumstances and I would just pull her off the road for 6 months. The 4x4 conversion will happen but its gonna be a johny cash "one piece at a time" I need the truck to work right now so good trans and updated brakes are number 1. From there it's complete other projects while updating the 57 on down days. I reached out to Orrie G for a little guidance on the steering conversion. If all works out the truck will be a 4x4 this year. I have wood and gravel to haul so repairs are day after it rains and to muddy to work. Slow switch over but as the parts are finalized they will be swapped over. Still need some dually drums for 3.5" shoes. Also have a rebuilt 400sb ready to be put on the stand to verify parts( been stored for 6-7 years and I have CRS). I am racing the year, weather, and shoulder surgery to get the drivetrain done. The 57 is about 2 or 3 years from coming off the road for body restoration. She is my dream truck but also a work truck. Finalize the drivetrain and build a shop before metal work since I am tired of working in the mud.

Sorry I deviated. I will check the steering box in the next few days and report back. My current box has 6" of play after adjustment.

[burnin oil]

Update. The front axle is under the truck now and the steering alignment is horrible. The steering arm on the box is probably 5-6" above the arm on the axle so I ordered a 4" lift arm for the axle and try and figure out the connection at that point. Still open to any suggestions here.


The 370 steering box is very similar in appearance but it about 20% larger. It looks like it will fit with new bolt holes but I will try rebuilding the factory box first. The 370s steering arm has the old school rebuildable tie rod end made into it which would be a challenge to work with.

While waiting on parts (front gears) I started doing the brake up grades. The front has the big bore caliper discs so the rear is getting the 3.5" shoe drums. While swapping out backing plates I found a cracked leaf spring. Luckily my 70 parts truck has a similar spring pack so those will get swapped in and reuse the 57s over load springs. Minor details are the devil.

[mat1968]

I have done it on a 56 3800 lift arm for 4-6 lift, ream stock pitman arm, make draglink out of two dodge 3/4 ton tiered ends. Flat draglink and drives good.

[dsraven]

you could always mount whatever box you want, cut the shaft and tube off, install a u joint like guys do when they clip the trucks but keep the old column. then the angle of the dangle is not so critcal.
hey, no pics-it didn't happen, haha.

[burnin oil]

Mat, thanks. Are the dodge tie rods from the 70s? Just want to be able to help my counter guy out some.

DSRaven, project was on hold for a couple of days. I had to do some work on the house and then it rained which wasn't in the forcast. All said other than some small stuff I was waiting on parts. The steering column is half removed for rebuild and I am working on getting the steering arm off the axle. I will try and get a shot of the trucks steering for you soon. The next couple of days should have my other e brake cable, axle u bolts and steering box rebuild kit here. Front axle research parts are here.

[mat1968]

Yes 70s dodge 3/4 ton , much shorter shank than a drag link end.

[mat1968]

Pic

[mat1968]

Pic

[mat1968]

Try again

[burnin oil]

Mat, thank you. you have a geourgious truck! I didn't get into the front end today other than getting her back on jack stands. I spent the day fighting those king pin style bolts on the rear of the truck. Got the passenger side loose other than u bolts and the donor springs disassembled. Did some other small things between heat cycles and penetrating oil. Here's a pick of "mator" sitting on jacks so the bumper is a few inches above ride hieght.

[burnin oil]

Update. I worked on the rear of the truck replacing the leaf springs and adding the lift blocks to level the truck out. I also got the 3.5" brakes installed other than running new lines. I had ordered a steering box rebuild kit from Eklers and took the day before the rain to pull the box down. No oil left inside and a roached bearing. It looks like I made the right decision to fix it now since I don't think there is any permanent damage. My only real question is how do you get mud daubers inside the steering box??? Other than that the box is drying from soaking and wire brushing.. I should be able to start replacing the bushing tomorrow and then its reassembly time. Next week I will have to hit the part store for lube, a rubber brake line, and working out the drag link equation. Once the weather clears I need to take a few days off of the truck to do some house maintenance and redo the jeep rear. Once I get the front end worked out I will put a post up about what I used. I want to leave a record for the next guy who does a conversion.

[burnin oil]

Update. The dodge tie rod seems to work. There are 2 sets for a 70s dodge and it used the smaller one. Ended up with that and a factory 70s chevy at the steering arm. I haven't drove it yet but it fits and seems to be correct as far as fit and In plane when coupled with the 4" lift steering arm.

I Ran all the new brake lines other than the master cylinder to proportioning valve but need one more rubber line. The drive shaft is reworked and reinstalled now so it is minor odds and ends at this point. Hopefully a shake down cruise will happen in the next week or two. I have had some problems and have wait on parts.

[burnin oil]

UPDATE for future readers. All seems to work well. The truck has a minor amount of bump steer off road but I am perfectly happy with it. Seems like this is the setup. Unfortunately the dump bed broke so she is down getting the new dump frame grafted in and reconfigured for power up and down hydraulics. I also have a leaking seal at the rear brake.

Over all the conversion is perfect and we'll worth the time. She performs flawless. Even with the manual steering and brakes. The factory master worked with the disc brake fronts and 3.5" rear shoe upgrade. Life is good.