Amazing show, I've been fortunate to be there every year. Vintage trailer heaven, plenty of nice rods show up too!
I have rounded up parts for a couple of years now to build one of these trucks My plan all along is to build a 1947 404 model 4- door truck on a later model chassis with a cummins 6 cyl turbo diesel and a allison automatic tranny You have done an amazig job on your truck and I am empressed to say the least! I have 3- whole cabs and doors, one cab that has been wrecked that is damaged, and a really straight 404 model front end My plan is to sit the body on a 87' chevy 1- ton chassis and build or buy a hodges style ramp bed for it to haul hot rods around that we build Your post has me really motivated to get started on my truck Scott
Yeah, update us please! I was running eastbound yesterday between Bakersfield and Barstow and saw what MIGHT have been this truck heading west. The truck I was a Diamond T, flat black, with a flatbed with a slippery lookin' street rod on the back. Been trying to find something on it ever since cuz the wife went NUTS and wants me to build her one! LOL
Yup, I haven't been here in a while. Kids arrived, sold the silver streak trailer and I got started on/completed another project... Took ~6 years so far but it's done, it moves the family: 1955 Flxible Visicoach with 1993 Cummins 8.3c, MD3060 Allison, air ride front and rear, lots of other stuff that deserves it's own writeup. I mention it to explain the absence from the DT but also I've learned quite a bit in that build... And now it's time to get back to the DT.
That wasn't me, but if you need direction on a build lemme know. Oh, and your wife has fantastic taste- good choice there.
Since 2011 then I've learned... Quite a lot about big stuff. The current issue that needs to be resolved is the front axle. Original brakes are not good enough, tested that already. Axle width on the DT is ~64", Isuzu NPR (of which I had one, DOH!) is good, yet most everything with 10-lug wheel hubs is too wide. I had a set of custom kingpins and bushings made to adapt the original axle to International 4600 corners with juice disk brakes. This is absolutely an option, though having driven the bus with air brakes I'm tempted to go that direction. Also, the original axle requires original size front springs (erm, gone 2 moves and 2 kids ago) on the original tapered frame.
There is a guy on my Diamond T trucks facebook page that used 1-ton chevy front suspension (IFS) and he said it bolted right on with only a little drilling.
Depends on the model and year of truck. I used an 1986 square body 1 ton dually front cross,ember bolted to diamond frame, 1 ton dually leaf springs bolted to diamond location. My truck is a 1948 509 wide axel. On Steve Stanford s face book page is a possible paint version , he is going to do another. I’m not on any of those type forums,
Yup, that's also what I did, except I narrowed it by 0.5" to fit the tires under the fenders. Fitted air bags and drove about 5,000 miles on it. Again, after doing the Flxible I have learned a lot and the Chevy suspension is both class 3 and has insufficient travel. If anyone wants to buy some IFS parts, I'll have quite a few ready!
Now, the fresh running gear donor. 1991 NPR stakebed. It ticked the boxes: Turbo diesel, disk front brakes, decent bones to start with.
Major surgery. Removed the cab and rear framing. The stakebed is planned to be narrowed and shortened, nice heavy unit there and will make a good platform for a real working truck. I'm not into hot rodding, don't need speed (if you know what I do you'll understand) but want an honest, capable and solid truck with class 5 capabilities.
Lots of stuff removed from the front. Need to shorten the frame by 24" so quite the planning needed. Steering box needs to relocate inside the frame, the one mocked up in the picture is from a E350 van. Fun part is that I need a ø27mm ball for the Isuzu steering link, Ford are ø28mm in their tie rod ends.
Turbo and cab are fighting for position, I need to run steering linkage and brakes up here. Brakes might be able to mount under (the original DT had this) but what a pain to service. Unfortunately, Isuzu did not make the studs on the manifold mirror image, so it can't just be flipped. Fortunately, the turbo can move with a bit of welding and fab work. Still considering location, here's one idea: Other options are to weld a new flange onto the manifold forward of the current location, make a relocation pipe or create a new manifold completely. Ah yes, if my 3D printer could just do Inconel 618...
More detail of the front of the frame which needs removal... Fender roughly in longitudinal position, just splayed out to clear the frame rail
The tires which came fitted to the NPR don't fill the wheel wells. I can possibly live with the 6-8.75 lug pattern, but tiny wheels on a big truck look wrong. Having said that, the current truck has a good turning radius, and my last iteration creates the need for lots of multi point turns. One issue is going to be steering linkage clearance for right turns, and leaf spring clearance will determine both left and right turns with larger diameter tires. Current diameter with 245/75R16 is ø31.7"; The 235/80R22.5 on the existing setup that look reasonable are ø37.4" so we are looking at 3" more tire causing interference in the radial direction. Looking at the pictures below, well, something will need to change:
I got lucky and bought the wide axel version. Since I was so ignorant on diamond t trucks , I thought the 3 inch piece spot welded to each fender was and added later. But Tom Warren in Amarillo educated me , that I had a wide axel. Last year I bought a second truck for parts , big difference from mine.
Am interested in the details on the wide axle, I'd assume standard modern width. Do you have any measurements drum to drum?
If I understand your post correctly, you would prefer to use the low profile 22.5” tires that have a 6” greater diameter than the stock NPR wheel/tire assembly. You did not mention the effect that diameter change would have on effective gear ratio and in turn, performance. If I am correct in my interpretation, what are your thoughts on that?
I shipped 4 pallets to Amarillo, all suspension, powertrain, wheels etc. I can just say that 3inchs were added to the fenders and I think running boards, We made new running boards, because I stretched the cab and doors 10 inches . There is a rendering on Steve Stanford’s site. If you were to call “Diamond T Rubber” , Tom could tell you the width.
Well, need to stay narrow so they won't be low profile to achieve that diameter (235/80R22.5) but that serves my purpose to achieve economy while going down the road. It's not a hot rod, no intention of smoking the tires- this is a working truck, can bring pallets of bricks home, carry machinery around and more usually haul my 1950's camper with some motorbikes to head out to the desert for a weekend. The current iteration gets 22-25mpg with the 6BT while towing an airstream, pretty fantastic. I'd like to have similar capability with the 4BD1T and so am planning to gear for BSFC (1800-2000rpm) at 55-60mph. Pumpkins are available in ratios from 4.10 to 6.1; Should be plenty of bolt-in wiggle room for final tuning. NPR's typically quote out around 13-14mpg but have a 15-20k# capacity and certain acceleration requirements. That fuel economy to me seems very low given the current capability with the 6BT. No free lunch of course, and since I'm not going to carry that kind of weight around can sacrifice fully loaded acceleration capability for fuel economy at cruise. To gain some of that acceleration back, I'm updating the turbo to a TD04HL19T (wastegated, more efficient curve, thank you tuner forums) and adding an intercooler from a 4BD2T. Target boost will be around 25psi, should bring the power up in the 275hp range so that when I do need to convert diesel into fun it's as easy as pushing harder on the accelerator. At cruise speeds the motor is operating at BSFC and when the boost drops off you have your economy target. Voila, at least on paper...
Interesting, and will do. Speaking of DT rubber- I miss talking with Bodie Cummings, he was quite a knowledgeable guy for these trucks.
Scott449....thank you for the explanation. I understand. My use of the term ‘low profile’ wasn’t quite accurate......I should have just referenced the difference in diameter and let it go at that without an adjective. In any case, the availability of alternative gearing answers my concern and your comments are appreciated. Very cool project.
Got some time on the project over the weekend. Got the steering box installed, 2001 Ford E350 unit. Elected to put it on the inside of the frame rail, so boxed what was there after making space. Still need to finish the mounting, two of three mounting bolts complete but the radiator cross member needs to go in to pick up the third. As tight as she can be...
Next step was the pitman arm and steering link. Found a forged 4" offset unit that would clear the springs. Then it was a matter of connecting the pitman arm to the Isuzu steering ball. Spent some time on the lathe turning a 1"-18tpi LHD to connect the Isuzu end to the Ford parts through an adjustable turnbuckle. Really happy with the results, it's clean and solid.
Radiator core/nose support was next. This took a while, as we wanted to ensure the front end was tied together correctly and the frame components were all supported through the cross section. Removed quite a bit of the donor front frame.
The Jalopy Journal
