hyd power steering info

several people have asked about my power steering so here is the basic info. you need to be capable of fabricating the bits needed to install it.

the best fit i have found is a saginaw 710 box from mid 80's internationals. this is a dual piston box and is very common. used with a 800 series upper column, and a 800 series steering wheel ( 18" od ) or you can make a column from your old box parts, and a five ton pump then all you need to fab is the inter connect shaft and lines. a mounting and bending template is available if you really need one. the top bolt goes above the frame , i added a plate above the frame at the same time i filled in the cutout for the old box. i had a piece of 3/8" plate press bent to match the inside radius of the frame, you can see it in the 2nd picture. you need to reshape the 710 pittman arm and rotate the drag link 90 deg and make it 1/2" longer but it is the same taper as the steering arm so that is a plus. next time i will thread the outside of the drag link and put an adjuster on it, more legal and gives some adjustment. you can palm steer even sitting still with the smaller steering wheel.

updated info on 02/15

Tom,

Can we get some additional shots of the rest of the work described above? I'm seriously considering replicating your effort...just can't part with $1800 for an air-o-matic.

I would love to see how that 5 ton pump mounts up too...

Great work on a great truck...you're setting a high water mark for many of us...

What criteria did you use to determine the use of this PS gear over others? I'm guessing that size is a consideration on this, but maybe not as much as I thought as you made it work outside of the frame. How deep is that box from the outside end of the pitman arm rod to the side wall of the frame? Also how long from the bottom front face of the box to where the U-joint is on the shaft?

I am trying to compare it to this other pump I ran across the other day.
http://www.steelsoldiers.com/index.php?name=PNphpBB2&file=viewtopic&t=15091

Hi Tom,
Excellent info as always. But, I have a question that relates to the relative superiority of that self contained box. I have a setup that I'm considering swapping on that I'll ditch if you can make a relative judgement on. On with my question, if you please:

Initially, I have done the same "outboarding" of the steering box, to clear the 3208. This is with a steering box from the L8000 that donated the 3208. It's a great ratio, although turning the wheels on flat pavement is a non-starter. It's also a bear if you're maneuvering in tight spaces, yadda yadda, you know the routine.

Now, I've sourced out a Ford ram-assist system, which uses a ram that engages the pitman halfway, and then bolts to the frame aft of the steering box. This ram receives power from a valve that rides "above" of the steering box itself, more aptly described just upstream of the box, where the steering shaft rides.

Do you know anything about these types of boxes? I like it because it shares mounting patterns with my existing box, and the ram assist thing appeals to a person who always worries about steering box mounting points. But, if your international self contained box is known to outperform a box of this type, I'll bite. Any ideas on this other type?



Oh yes, as a general contribution to the thread, I put together a system that would probably be of interest to anyone looking to setup an outboard steering arrangement. I found that, after chopping the long steering tube (as well as the guard that literally bolts onto the stock box), the steering tube became "floppy". So, I attached the steering tube "guard" to the firewall. To effect this, I welded two straps of 1"x.250" bar to the tube, one in the horizontal and one to the vertical, and made essentially an "L" (with some additional gusseting between legs), where the steering tube is at the bottom corner of the "L". I then put two small bolts along each leg of the L, securing it to the firewall.

Now, once you chop the steering tube, you're left with a need to connect it to the new steering shaft (I used the donor shaft that came with the box). I'd say that you really want to grab that part if you can get it along with the box. Anyway, to connect the two, I found a PTO yoke that welded onto the steering tube and was a perfect slip fit for the tube guard, and was the right U-joint to boot. It was very elegant, and the stock shaft is actually collapsable as well between box and firewall.

I love threads like this. Always an inspiration, Tom.

Ok, maybe it was the two hour run I just went on, so I'm a bit gushy, but Tom was the guy who originally gave me the idea for the 3208 swap, and who talked to me for the better part of an hour about the 3208 and spicer trannies etc.... a real, real help.

Best,
Bob

i'll take some more shots............. the five ton pump just goes right in the front of the timing case in place of the plate that is there now. you will have to trim some sheetmetal from the fan shroud to clear. i liked the 710 box because it is common, selfcontained and most of the pittman arms and drag lings that you will find with it on internationals like s1600 to s1800 and many others lend themselves to use with just a little tweaking.i have never had to o/h one but have had to replace shaft seals on one. o/h kit is about $50. box is usually about $150, pump may be about $200, upper column will be from $50 to $200 depending on how you go about making it. there are shafts on gmc and chevy delivery trucks that use a saginaw box that have all the parts for the connect shaft, you just need to lengthen it.

Great, thanks Tom!

Any details or help on the parts you made for this would be wonderful. I'm really wanting to do this...

i added more pics, go back to the top for them. in the frame pic you can just see the rear edge of a reinforcement i put behind the box area. i had it bent to match the inner radius of the frame so it would be a close fit.

What size tires are you running? Wanting to know if it will clear 15.5's / 395/85/20's with the box on the out side of the rail.

Thanks for the info Tom. Outstanding!

What is the resevoir from? Is that military or from the donor vehicle?

Re: RE: hyd power steering info

sermis said:

What size tires are you running? Wanting to know if it will clear 15.5's / 395/85/20's with the box on the out side of the rail.

Click to expand...

Do you thing the larger tires will hit the box or draglink? They don't hit the Air-O-Matic link but did not know if they would hit the box outside of the frame.

RE: Re: RE: hyd power steering info

Trango, I've seen the style that you've referred to with the hyd ram pushing on the pitman arm. I've seen heavier applications where it has that, plus an additional ram on the axle. I'm a BIG fan of having that ram axle mounted. On my big M715 I have a Saginaw PS box that I tore down completely, drilled and ported so that I could use a ram assist with it. Now that truck is only 8000# but it has the front axle locked and 46" XML's on it. I can palm steer that lock to lock, sitting still, on dry asphault. Power steering is great, but as tires sizes increase and people's offroad desire increases, I have to think that all that input from a stand alone power steering box is turning big tires on a heavy truck thru four studs on the top of one knuckle. I would lean more toward finding a system like trango described with a ram assist already, BUT, find a steering arm that is stock like length then plum the ram onto the axle. My other truck has two tabs welded to housing behind the axletube on the driver's side of the diff, then two more tabs welded to the driver's side of the tie rod. A simple 9" travel hyd ram does virtually all the steering work acting on fluid metered down to it by the ported PS box. This set up allows long happy life of steering components as virtually all the big steering stress is taken off the linkage from the box to the knuckle's arm and 4 studs and placed directly on the housing, ram, and tie rod. I have only a simple Saginaw PS pump with minor flow modifications running this set up.

RE: Re: RE: hyd power steering info

Could you use a pump from a 3/4 ton truck and belt drive it?

RE: Re: RE: hyd power steering info

my wheels have 1" more offset than stock with 14.5r20xl's and clear by lots. also stock 9:00-20 will clear. resevoir is form a chevy van, used just the end caps and put in 4" tubing to get it longer.

Re: RE: Re: RE: hyd power steering info

comdiver said:

Could you use a pump from a 3/4 ton truck and belt drive it?

Click to expand...

I do believe you could do that. I have. Most of the medium duty trucks run seperate systems for steering and braking.

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Hey Spicer, thanks for the feedback. I hadn't thought of using an axle-mounted ram - but it makes plenty sense! This is far off in the project mix, but I may get there late 08 or so.

BTW, on the buggy that I might actually finish one day, I have full hydro steering, and a double ended ram on the axle that turns the 53's with ease.... it's hot stuff.

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I'll try and snap a pic of my ram set up today and post it.

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super truck dan send us some pics of the truck would love to see TIm

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nice job but it's a no no to weld anything to the frame rails. in due time you will get cracks at the weld

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many trucks come with welded frames, how do they do that??

RE: Re: RE: Re: RE: hyd power steering info

If the frames are heat treated, you don't want to weld them. I have welded countless frames over the years with no issues. Use the proper rods to avoid hydrogen embrittlement and you are fine. I don't think deuce frames are heat treated, that started to become common in the late 70's.