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I have just been offered a C70 with air brakes and a Gmc V6, I also have access to a 51 2 1/2 ton thats rough but complete, I have a 48 one ton as well. I want to put the V6 and rest of the drive train from the C70 in the 2 1/2 ton and the 48 cab on it and use it as a tractor to pull our pulling tractors to local events. The C70 has been used as a plow truck and is really rusty but it runs like a clock. I think it would look really cool with lo pro 22.5's on polished budds on the front a small sleeper and air ride in the rear. I also have access to a 13 speed road ranger which would help the V6 on the hills stay in its torque range, gas mileage would be attrocious but I wouldnt be going much more than 30 to 40 miles a few times a year any way. It would be cool to see something different than the usual Mack B models I usually see, I love B models but this would definitely be neat.

I got a GMC V6 in my 62 fire engine and love it. the truck is 12,000lbs and I can start in 3rd on a hill, it pulls! the v6 is rare today so its cool to see one.

I think you'll find that the RR 9-13 series will not work with the V6 bellhousing unless it was made for a heavy trans. RR's were also made for gas engines but the two must be compatable is my point. If it is an O-T-R diesel tractor tranny then it will be far too heavy plus other considerations. Grigg is best to take this up with, he's pretty knowageable about this stuff.

If you want a 13 speed, you need to look for a RT613 in a direct or a RTO613 OD. They are made for mid range trucks.

I went back to the C70 today with some bee killer and killed several nests. I found its a 1968 and it has had replacement longblock 401 Magnum in it. From what I understand the industrial bell housing adaptor and flywheel can be used to adapt a fuller, I was a heavy truck mechanic for 15 years before I went to work for the Railroad to work on cranes and other heavy equipment, but I have never seen these 2 coupled. The truck has an electric shift 2 speed rear and a 5 speed so I think I am going to keep what it has as far as drivetrain goes. A plus is that it has power steering too. I thought about dropping the 48 cab and 52 nose on this frame but I think it would sit up to high , at least 8 inches higher than it does now. The V6 looks to be a little bit larger than a small block so I should be able to squeeze it under the hood, gotta get it home and get out the tape measure and do some measuring.I wasn't looking for a project right now but this kinda fell in my lap and seems to neat to pass up. T.J.

GMC made a kit in the 60's to repower early 50's GMC trucks with a V6 so it has to be doable. All they did was fabricate motor mounts. I don't know what they did with the steering box. The steering box is a problem with a V8. I have only actually seen one. The GMC dealer here did the conversion. The owner didn't keep it very long. He bought a Chev with a 409. Wasn't very long, he fell asleep, hit a tree and killed himself. I don't know what ever happened to the converted GMC.

The thing that would make the most sense to do would be to put a newer Brigadier cab on the C-70 but then it would just look like a Brigadier with a sleeper when its done, plus I have no attachment to the C-70. The 52 I have been around my whole life after it got vandalized (the windows and gauges and all the lights got smashed it was driven to the corner of the field and has sat there ever since around 1972 or 73) it was my jungle gym I put thousands of imaginary miles on that truck,I am sure I wore the shifter forks out too. Unfortunately with no windows for 35 years or so and lots of wet leaves its pretty well shot. The 48 cab is still pretty decent so between the three I could build up a neat old truck that would make 3 old friends happy to see their old Iron return to the road at least in pieces, unfortunatly only one of them is still with us.Another plus is its an AD truck Nuff Said and lots of body parts and trim pieces are available not so much for the C 70, and the AD truck just has perfect lines They are an american Classic unfortunatly the C 70 will always just be an old truck , just my opinion of course. T.J.

Back when I was building pull truck engines, I had ideas of setting up an exhibition truck with a GMC V-12 for power. The cold hard reality of the impossibility of building a high-performance V-12 trashed that idea. We campaigned a Dodge chassis with a roller-cammed 440 in the Super Stock class for several years. Class rules specified one 4-BBL and gasoline, but I still managed to get 700+ HP on the dyno. I also built blown hemis for the Douthit family's "Big Mama Magic" truck for some time. Our biggest one was a dry-block hemi that came out to 547 cubic inches after a bore and sleeve job. Larry Douthit won several pulls with it before he got greedy and turned up the boost. It put the crankshaft out the bottom in three pieces!
Jerry

Not to change the subject much, but these folks claim to be doing it, and asking a fair amount of money too..
http://www.thunderv12.com/

Grigg

There is no question that V12 can be built into lotsa power with lotsa bucks. However, I think onetunn is trying to build something out of components he has...401 V6 with a 5 and 2 with electric 2 speed, straight air and PS in a cancer ridden 70 series. In my opinion, these are very desirable and very flexible components. Putting a Brigidier cab on it shouldn't be that difficult because both have 34" frame and the tread widths are the same. It sounds like the old 51 may be too far gone to be a candidate to easily restore. I would recommend a Brigidier cab if he likes them and then finding an early 50's in better shape for his next project.

Hey Crenwelge, I think I have my game plan figured out for now, I just got a snow plow for the C-70 I am going to weld in some floors in the cab and put Farmer plates on it and use it around the farm and hopefully work out all the bugs in the drive train because after sitting this long there will be bugs, make it safe to use, but not pretty. Then I am going to start on the 52 figure out my wheel base get the rear suspension all set up Probably Pete air ride, strip all the sheet metal and do all the bodywork to the cab and sleeper and then strip out the C-70 into the waiting 52. And hope fully not get divorced again in the process! Thanks T.J.

I did look into a brigadier cab but you are talking aroung 1500.00 for a decent one, it is the same cab and will bolt right on, but I dont want to end up with 2 trucks in the end. T.J.