Front Leaf Spring Suspension Source Questions

I used to be a class 7/8 mechanic, that worked on 100s of Internationals, I would hazard a guess that:

make different front drive axle spring hangers for different 4wd Loadstars (or any other truck brand) that will interchange?

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you will never get an answer on this forum for that. imho, You would be far better off looking for the answer on a corn husker site or even a dedicated Scout site. You are far more likely to come across a group (3-4) of people that might have actually worked on one or owned one.

Loadstar front drive axles have their spring hangers to the side of the frame, not under the frame like 2wd Loadstar's

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Have you checked to make sure the steering boxes are the same? Just to give an example, on some 1970s Ford F-100s, the steering boxes for 2x4s and 4x4s were 180 degrees opposite each other concerning the pitman arm.

And a 12 stack of springs seems so overkill for the front, especially considering my 2wd Loadstar only has 6 front leaf springs 3 in wide mounted under the frame.

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Just because you have more leaves or thickness in the pack, does not mean it was a drastic increase in weight capacity. Any S-1700 is going to have a limited weight capacity, it is why they are 1700s, you are not going to find one with a GVWR of 33.000+ pounds. The thicker pack was probably so the axle would not submarine under torque. Your 1969 might not have power steering, your 1976 might. The thicker packs might have been needed to compensate for negative road characteristics at speed.

Pictures would have been nice, at least to gawk at.

After 1972 and the new FVMSS standards there was a huge change in vehicle designs. To deduce what a suspension was designed to do from a description on a vehicle 54 years old is a futile effort. I have seen literally seen and sat in 1000s of tractors including from extinct brands that I can't even recall at the moment. Except in pictures (school bus e.g.) I have never seen a 1969 S-1700.

I have a nice '69 Loadstar 1700, no rust with only 15k original miles.

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Pictures would have been nice, at least to gawk at. Especially the interior and dash.

Thank you for your replies. They are helpful.
Attached is a picture of the 1976 truck the front axle is coming from. I don't have a picture of the truck it's going into because its raining and that truck is under a tarp. But it looks almost exactly the same including the same color. It just has no rust and only 15k original miles. My intended use is for wilderness camping.

This donner truck is a lot more dirty and rusty with years of caked-on grease and road tar than the picture would indicate. It also has a big crack in the frame just under the cab. So it's good only as a spare parts truck. Except for the front axle and transfer case, everything from the engine to the rear axle is exactly the same as on my good 1969 Loadstar.

Just a technical point, these trucks are both an International Loadstar 1700. The Loadstar S-1700 models came out in 1978 and is a complete redesign. They're a little wider and the engine compartment is longer to accommodate the larger diesel engines. Nothing will interchange between a Loadstar 1700 and a Loadstar S-1700. But almost everything will interchange between the 1962 to 1976 Loadstars.

Most parts for the Loadstar are now obsolete but so many were manufactured over such a long period of time that some places still have lots of surplus NOS parts.
I've already bought all the brake parts and kits, seals and gaskets, pins and bushings, wheel clamps and studs etc. I might possibly need to rebuild the front axle. And that includes two complete NOS locking hub assemblies for $108 each. . . . Everything I need to bring the axle up to the level of my good Loadstar, except spring hangers.

Again, thank you for your help and suggestions.

total newb said:

No mdt mfg makes any of the trucks in 4wd, they are aftermarket converted.

Dollars to donuts those frames are the same outside width. Transfer the brackets as i said.

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I suspect you are correct. Probably nobody knows the difference between a spring hanger made for a regular frame and one made for a reinforced frame using the same axle assembly. Perhaps the mounting holes are slightly different, although I doubt that because back then IH drilled all their frame rails to be used as either 2wd or 4wd. I converted a '62 IH pickup to 4wd and the frame was factory drilled for the transfer case cross member.
So perhaps the hangers are just more heavy duty for a truck with a reinforced frame.

I'm beginning to realize my only two choices are to either buy a hanger made for a reinforced frame then take careful measurements to find the differences between it and the ones on my regular frame truck before I buy three more.
Or just suck it up and get under that truck and start chipping away at the grease and road tar to find the rivets then start grinding away with a rotary file.

My advice to anyone attempting a restoration like this is to get a parts manual and go to the "Wisconsin Historical Society" and get a "Line Setting Ticket" for your particular truck. Then google using part numbers. The W.H.S. has the L.S.T. for every IH vehicle ever made in the U.S. until 1980. The L.S.T. has the codes you need for your particular truck to use the parts manual.

As a technical side note: These axles were designed by NAPCO and built by Dana/Spicer exclusively for International Harvester. They're unique (not Dana 60 or 70 etc) to International Harvester. To back this up, there is a data plate on them that says Napco. The yoke (turning knuckle ball) is larger than a Dana/Spicer 70. I was able to get a parts list from Dana for this axle. The seals, felt, bushings etc are all still available directly from Dana knowing their part numbers. These same parts are also still available directly from Navistar for almost exactly 3 times the price sold by Dana.

So perhaps the hangers are just more heavy duty for a truck with a reinforced frame.

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The older trucks (not talking light trucks such as F-series) I have seen with a "reinforced" frame were literally double framed with a smaller channel inside the stock frame. They probably used shipping channel. I doubt many OEM's bent their own channel and formed it. So, if you measured the back of the frame the web would be 1/2"+ with one channel nested inside the other. With stickers plastered all over it saying "do not drill or weld flange". A truck with two frames is going to weigh much more then a single frame, so, I imagine the springs and hangers have to account for it.

So, a spring hanger (for ones with leaf springs) would attach in the same place, but, the bolts and rivets are longer. I can't speak for a 4x4 front because the International 4700 4x4s were few and far between, they usually had front bumpers, and I did not look at them at length. I do not remember ever driving a 4x4 S-1700 or 1700 (did not know the "S" difference until you posted).

The side plates carry the whole load and locate the axle, so., if you step up from say 3/8" to 1/2" thickness, that has to be accounted for within the spring hanger. Which means the spring hanger has to be larger and thicker to withstand the sheer stress.

Loadstar front drive axles have their spring hangers to the side of the frame, not under the frame like 2wd Loadstar's.

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Especially if the hanger is located outside the frame instead of under it. If you measure the shackle straps/side plates, they are probably much thicker on the 4x4.

I was going to show an example from e-trailer, but, the shackle straps for a triple axle trailer are thicker then a single or dual axle.

It would be interesting to note if the eyes of the springs sit higher on the 4x4, above the lower flange.

--> Does your 2x4 have the frame reinforcement that the gas tank attaches to on the 4x4, that look like it comes from the front and stops before the rear tire?