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1958 International Harvester Receives A Technology Transplant (PART IV)- Extracurricular Projects

58 IH w- Jeep350.jpg

It’s been too long since the last update (Sorry). There has been a lot of work coming in the office and my boss keeps telling me that it has something to do with me earning a living. So, that has taken priority but in the mean time I’ve been saving up for things like ‘axles’. Oh, boy! How many of you actually get excited when you hear the word axle? Yeah, I didn’t either, until about a week ago.
Anyway, Last time I left you guys we had boxed in the frame, stuffed the 2006 GM 6.0L, 4L80E transmission and New Process t-case inside the shell of our ’58 Travelall and bolted up the mass air flow meter. We had a couple setbacks…
– Transmission cross-member fabrication (ran across t-case output)… Refabricated cross-member to go up and over the output shaft
– Driver’s side header did not fit (now running 1998-2002 LS1 Camaro header on driver’s side and 1969-1972 (LS1 swap) Chevelle header on passenger side (both from S&P in Arkansas)
…but I should have known my education was just beginning.

No New Radiator? No problem…
We received the 1958 IH radiator back from being re-cored. This being a ‘four-wheel drive tank’ we thought it best to move forward with re-coring the heavier but more durable 3-row brass down flow radiator with 5/8 tubes; silver soldering portions of the tank to seal everything up tight. After pressure checking it for leaks we bolted it up to the front fascia, took some measurements and headed down to the local auto parts store for the inlet/outlet tubes. The Goodyear ones we found were probably destined for some obscure vehicles built back in the 70’s or 80’s but they worked almost perfectly.
After receiving the radiator back we proceeded to clean up the front clip and rebuild the front end (fascia, quarter panels, hood, etc.)


Fuel Tanks – It’s just a big steel (or plastic) box I fill up with gas… right?
Well, as it turns out there’s more to fuel tanks than one would think. There were a few companies that I looked into when deciding on auxiliary (or aftermarket) fuel tanks. I eventually chose ‘Aero Tanks’ who knew the fundamentals of fuel tank construction. The dimensions of the tank were important, but the location of the tank within the vehicle was paramount.

Building a fuel tank that would sit just in front of the rear axle inside the frame rails would have been perfect, but the frame rails on the IH are too close together. Late model truck frames tend to bow outward once past the firewall, but the 1958 IH frame was straight as an arrow. This meant that the fuel tank needed to be really thin or the driveshaft would have been too close for comfort. I really wanted greater capacity… I’m not talking 16 gallons, but more like 30 gallons. I’ve heard the 6.0L small blocks are pretty thirsty and stopping for fuel all the time could get monotonous. So, it was on to plan B.

Positioning and Mocking Up
After coming to terms with the fuel tank not fitting inside the frame rails (in front of the rear axle) I tried mocking one up out of cardboard behind the rear axle. This brought up other issues such as departure angle, fuel-sending unit positioning (it was tall – 14 inches) and fuel feed psi (distance from sending unit/pump to engine). There had to be a better way. So, I ended up taking measurements and mocking one up out of cardboard on the driver side where one of the original IH fuel tanks had been mounted on the outside of the frame rails. Not only would this work, it would line up with the fuel inlet tube through the body. My plan is to counterbalance the weight of the fuel tank with batteries and the exhaust system (mounting those on the passenger side of the vehicle).

Body off frame – raised about 6 inches for fuel tank installation

Did You Say Baffles? I’m… Confused…
In designing the fuel tank we decided to mount the fuel sending unit towards the back because that meant when I’m driving up a steep incline on ‘reserve’ the engine will not be starved for fuel (I can always freewheel down a hill – right?). We also wanted to keep the fuel from sloshing around inside the tank. The original tanks were just metal hulls with a sending unit. The new tank would have baffles which is really just a fancy way of saying partitions that separate sections of the tank which only allow minimal fuel past at a slow rate.
Front of tank.jpg

This new fuel tank would also need a relief tube, which would allow air to escape when filling up. This prevents ‘blow back’ (out the inlet tube when refueling) and increases the rate at which refueling can be done. There was also the issue of a drain plug, which would allow me to drain the fuel if there is ever a fuel sending unit failure – you can drain it before dropping the tank (31 gallons at 6lbs. = 186 lbs.). You also never know what could happen down the road. Maybe someone will run out of fuel miles from the nearest gas station and is in dire need of a gallon or two from my tank? Mom borrows it and fills it up with diesel instead of gasoline? The list goes on and on for that little $1.50 drain plug…
Fuel Lines – Plumbing
So now, thanks in part to ‘Aero Tanks’, we had a 31 gallon fuel tank (the original tanks were about 16 gallons each) with a ‘06 fuel sending unit (almost cost more than the tank) from GM which would plug right into the ’06 wiring harness.
Now we had to plumb fuel lines with proper fittings from the fuel tank to the small block 6.0L V8. This process requires special tools. The kinds of tools that you will use… oh… maybe once every five to ten years (if you’re lucky), but they are the kind of tools that save hours, quarts of sweat and pints of blood (trust me).

To pull the O.E.M. fuel lines off at the engine block you’ll need what we like to call ‘decompression rings’ which are used on ‘compression fittings’ like AC lines, Fuel Lines, etc. Your local auto parts store will probably catalogue them as ‘Fuel & AC disconnect tools’. They are used to decompress the spring inside the fitting. This is where it pays to have really nice friends. Those tools typically run about $40-$50 bucks, but if you have really nice friends who are nice enough to loan tools it’s an IN-N-Out burger, fries and a Coke! (Thanks Darin…)
Trans. Cooler/Oil Cooler
We also decided to fabricate a mount underneath the radiator (behind the stock IH louvers in the front fascia) to accept both a trans cooler and oil cooler (Again, friends good at welding up your custom designed mount really helps). After bolting the coolers in place I mocked up the length of the lines using rope; running them through the frame rails to their final destination. We removed the stock oil cooling lines running out of the engine and tranny and drove up to ‘Mesa Hose’. There they took my measurements, welded fittings to the stock GM lines and sold me (four) braided high-pressure lines for the oil and tranny cooler as well as fuel lines for the fuel tank (Fuel line + return line). We were all set for the next phase… hooking up the battery.
Shocking Revelation
As I reached for my ½ inch wrench with the chunk of steel missing from its side… I was taken back to a few years ago. I was underneath a ’56 Nomad changing out the battery someone had stuffed in a battery box underneath the rear seat. The genius who welded the battery box in place decided to make battery wire terminal connections only accessible from underneath the vehicle. So, if the battery ever went dead you had to crawl underneath the car and disconnect the terminal cables. I soon found that it is difficult to maneuver in tight spaces where there is little room for error. While unbolting the negative terminal the back end of the wrench ran across the positive terminal. That’s about the same time I came to realize what they meant by ‘800 cold cranking amps’. I’ve never really been the same since …

But in all seriousness I think electrical has to be my least favorite thing to work on. This project required some serious re-wiring. However, since we were running the stock fuel sending unit we ran the stock ‘body (wiring) harness’ down the length of the frame, connected the accessories box, BCM, TCM, and ran the dash wiring harness through the fire wall. It really was ‘plug and play’. (Special thanks to Laura for noticing the factory color-coded tape. How I’ve made it this far I’ll never know…)
Battery… or What Some of us Call ‘Juice’
On the ‘custom’ side of things we had to relocate the battery from the engine bay to the passenger side of the frame (there was simply no room in the engine compartment and weight distribution was a factor). There were four main components we needed to deal with: Accessories Box, Alternator, Starter, and Battery (not to mention grounding). They all needed to be connected to one another. The original wiring was about 4-guage (the lower the number the thicker the wire). We ended up running 0-gauge, pure, oxygen-free copper (I’ve been told it’s about 10 times better than the stock wiring).
Without filling the fuel tank up with any gasoline (I didn’t want to add ‘fuel to the fire’ should something go wrong) we ran all the cable and plugged in the battery. We plugged in the dash wiring to the ’06 steering column, grabbed the stock key from the ’06 GMT800, placed it into the ignition and on the first try it turned over. Phew!
Next it’s on to axles, leaf springs, drive shafts, wheels & tires…
Front axle considerations: Dana 44, Dana 60
Rear axle considerations: Dana 60, Dana 70, Corporate 14-Bolt
Gears under consideration: 3.73 or 4.10

Can you guess which axles we went with?

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