What in Tarnation?

looks pretty good for a hillbilly, and thats a fact coming from another hillbilly. what trans are you running, i forgot, looks like the gm bell housing. one of my 5.9's i had rebuilt and the cummins factory cream colored paint would not come off with two dunks in the builders caustic tank, so we left it on. keep up the reports, skip

It's a GM SM465 Granny low 4 speed. Pretty much a 3 speed ****** for all intents and purposes from an '82 one ton gmc. I used the same in my last 6at conversion which was a 59 f350 with a later sterling 10 1/4 rear with 4.11 gears. It would do an honest 80 mph (satelite speedometer) on the interstate, but the gears were too far apart for normal daily use. I think the 4.86 gears in my tonner will help and I rarely leave the island with it's 40 mph top speed limit. And yes, it's off topic, but so is a T5 or an alternator. At least it doesn't have a mustang 2 front clip or (gag) low profile 20" aluminum rims.
 
80mph without overdrive in a diesel with 4.11's ???? come on GB, if i lived closer we would have to debate that over a beer or three. my stock 89 dodge is wound up at 75, i cruse at 65 with the supposed to be horrible getrag 5spd od. 373 gears, i think, no proof, never checked. now, off topic?? denny, this thread has been up for two months, you know the content, if not to your liken, dont look, its that easy. to come in just to make a negative comment just shows us you have nothing else to do. i come to the barn every day. many days i am only here long enough to scan the first page, and if there is nothing pertaining to my cars, or some knowledge to gain, i am gone. no point in reading that which does not interest me. often i go next to the model t ford club of america. that too, like the barn, predominately talk about model t fords, but...almost daily there will be ot talk that is very interesting. it could be a cool antique boat some guy just got, whats the best trailer tire, how to fix a crank up wall phone or a player piano. its all fun, and when its of no interest, i leave without complaining that it didnt fit my interest that day. gb is a talented guy with a variety of projects which i am happy that he shares with us. maybe we should just have more "what kind of oil should i use" threads that go on for a week
 
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80mph without overdrive in a diesel with 4.11's ???? come on GB, if i lived closer we would have to debate that over a beer or three. my stock 89 dodge is wound up at 75, i cruse at 65 with the supposed to be horrible getrag 5spd od. 373 gears, i think, no proof, never checked. now, off topic?? denny, this thread has been up for two months, you know the content, if not to your liken, dont look, its that easy. to come in just to make a negative comment just shows us you have nothing else to do. i come to the barn every day. many days i am only here long enough to scan the first page, and if there is nothing pertaining to my cars, or some knowledge to gain, i am gone. no point in reading that which does not interest me. often i go next to the model t ford club of america. that too, like the barn, predominately talk about model t fords, but...almost daily there will be ot talk that is very interesting. it could be a cool antique boat some guy just got, whats the best trailer tire, how to fix a crank up wall phone or a player piano. its all fun, and when its of no interest, i leave without complaining that it didnt fit my interest that day. gb is a talented guy with a variety of projects which i am happy that he shares with us. maybe we should just have more "what kind of oil should i use" threads that go on for a week

Cas, unlike your 6bt and the 4bt cummins diesels, the 6AT was originally designed and built by Onan engineers. When Cummins took over Onan in the early 80s? they inherited this engine that was built for their generators. I know nothing of electricity but these generator diesels were designed to develop their rated hp at 3600 rpms. I think your dodge stuff was like 2200 rpms. Huge difference . The 6at is an IDI engine with a pre combustion chamber. They run in the same rpm range as gas engines. An 82 gmc with a 454 or a 350 would do 80 mph, we all did it with 4.11 gears (normal) and a big block/small block would turn 3600 rpms . I'm not saying my 59 f350 would pull Stevens Pass pulling a trailer at 80 , but between Mt Vernon and Bellingham Wa, I did an honest 80 and that's with a driveshaft sleeved and welded using the engine and drivetrain as my lathe. Honestly , the difference we see is the 2200 rpm normal cummins in the dodge and the 3600 rpm onan generator engine I have which cummins adapted for diesel conversion into delivery vehicles. BTW!!!! Thanks for your support on this. The correct battery cable for a '36 puts me to sleep. zzzzzzzz
 
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It will still go to the dump like it always has, but won't foul the plugs on the way home or fill the cab with blowby, like the worn out engine I was using.. Yes I coulda rebuilt the flathead $$$$, but this good diesel was taking up space in my shop and it needed a home.
 

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FYI, the full load governed speed of the Cummins 6BT and 4BT on-highway engines of the late 1980's is 2500 rpm.
 
FYI, the full load governed speed of the Cummins 6BT and 4BT on-highway engines of the late 1980's is 2500 rpm.

There are rpm calculators out there. My tires on the 59 were 33" 255 85r 16s. Gear ratio 4.11 . I'm guessing I was below my governed speed of 3600 rpms. In the treatise I downloaded on the SAE's site regarding Onan's development of this generator engine, they tested and ran at full load for 2000 hours at 3600 rpms under full load. They did this with 38 engines with no major repairs needed. They ran some under refrigeration loads for 20, 000 hours as well. All that aside, I have made some progress on this oddball project this week. Drained the gas from the tank yesterday and my son mowed the lawn with some of it today. Put 5 gal of diesel in the tank. Hoping for a startup tomorrow, maybe front clip on Sunday and deliver a load of beams to my ongoing supermarket remodel project early Monday morning. Maybe a bit optomistic, but if all goes well??????
 

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That is going to be one fine hauler when completed. It looks like all your engineering on the chassis is paying off on the installation in the actual truck.
The engine and transmission are probably good for 10,000-14,000 GVW.
 
wow, looking really good! is that the 9' box on the back?

No, the 122" wb tonner always had an 8' box. Only the '42 and later had the ability to haul 4x8 sheets flat and the tailgate closed. It's a beautiful spring day here and I have a couple of friends coming by. I have a few two man jobs saved up. The 9' box came out in '53 with the advent of the F350.
 
Drove it outa the shop today and took a few laps. Lost 1/2 a day and half a night chasing why it wouldn't start and tried 3 batteries....got outa bed at 4:30 am .......... Turns out it was a big thick red battery cable that I loved in my collection, and it must have had a bad spot. When I swapped it out, it fired up instantly like a brand new truck. ( I went from distraught to a kid at Christmas).....Maybe some of you know that feeling.Not going to be in a huge rush to install front clip until I know for sure the gremlins are worked out! Wife took a great video of me driving it but that has to wait til my 26 year old kid can get it up on youtube.... Gol dangit that battery cable... it took 3 years off my life!
 

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i too have a collection of big ol cables, some i'm sure would be questionable if put under a load. thats a great lookin truck GB, you will have a nice addition to the fleet
 
The front clip went on Friday after work... Then some sea trials. This morning at 6am before work I put the front bumper back on and after work my wife and my son helped me put the hood back on. Pretty much looks like an old faded red farm truck again. but with a surprise under the hood. I have all the ford gauges hooked up and they seem to read correctly with the flathead senders seated in the cummins block. Even the original ford speedometer cable threaded directly into the GM ****** seems to read ok. Oh, and big plus for us rural, no street lights guys is the GM Sm465 has a backup light switch. Gonna mount a really bright one on the rear bumper. It's so great to enter the modern age......
 
Worked in town all day on the grocery store remodel... Got home at 5, kissed my wife, grabbed a beer and went down to my personal jailbar junkyard and found an amazing 6 cyl type short air dam for in front of the radiator. This incorporates the hood latch and safety catch. Even though I changed position of the radiator itself from the stock 6 cyl position, it bolted right up and is against the front face of the radiator. Some days just end well with a bolt in and no cutting and fab work.
 
Been driving this heap for about a week now....Yes it is too loud, but with the stock gearing that I'm so used to, it just leaps up the long grades that I have tackled for 40 years. The Olga hill, Flarety's hill, Wollards Hill, even the S curves at Buck Bay.....Effortless in high gear. Now ask me again when I take it off island (pretty much never) and try to roll I-5 at 70.... Ain't gonna happen. I built an island truck and I live on an island. I have 3 good rigs from the 90's that I take when I gotta run to Seattle or East of the mountains. That means that about 90% of what I do can be taken care of with the '47. The other two rigs I had with cummins 6at power were geared for the mainland, and were slugs on our rural and very hilly roads. I am very happy with my build, but maybe getting a bit more deaf. Huh?, what?
 
Bit Deaf, eh?

I SAID A BIT DEAF, EH?

Glad it's working out well for the use you intended for it.

Mart.
 
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