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Hey guys,
It looks like I got that '50 3/4 ton long box bought. I would like to build a working street rod. I want to be able to tow a 12,000lb trailer. I'm looking for opinions on drive train and suspension. I'm estimating that 300hp and 350-400 lb/ft torque is necessary. An automatic overdrive trans is my first choice. I was originally thinking of a 6.5 TD or a Cummins 5.9 but am concerned about controllong noise and vibration. So my next idea is a big computer controlled gas inline 6, maybe turbo-charged? I've got a super-charged 3800 in my Pontiac SSEi. I really like that engine. I know I could get it done with a 350 "crate engine" or a camaro engine out of a bone yard but I kinda like the idea of doing something different.
On to suspension. It must set "right".... long and low!! I'm thinking of a dropped straight axle in front with air suspension in the back. I would like to use 16" "dually" alcoa wheels. Is it possible to mount the "dually" style wheels onto the original hubs? Is the original frame strong enough or should I consider a later model frame w/ independant suspension?
Thanks for any opinions!!!
Dean

The swap to a later model frame will be a lot of work. I would convert the front end to ifs from a 3/4 ton, and that will be a lot of work, too. The frame on these trucks is narrower. For a differential, get a 14 bolt corporate from a late model gm. If you want to run duals, you will have to extend the fenders and/or tub the bed to make things fit. For an engine, either go with a diesel or a big block v8, otherwise you won't have enough torque. I understand the 4L80E tranny is a great od auto, but I think it requires a computer controller.

Jeeze Fred - you beat me to it!

I have towed a 12,000 lb trailer quite a few times with a 3/4 ton truck that weighs about 6000 lbs empty. I have a high level of respect for the loaded trailer and what it can do to you going down hills and around corners and in heavy traffic. Your power estimates are fine. You should plan on a 4L80 transmission if you want an automatic and you will need an electronic box with it to make it shift right and a 4.11 14 bolt rearend with 16" tires will put 60mph right around 2100 rpm.

Forget using the original rearend and whimpy brakes. . . unless you have the flowers all picked out for your casket.

Getting 8-9 tons rolling down the road with a 3/4 ton truck is doable - but careful attention to suspension, drivetrain and brakes are a must if you want to do it safely and reliably.

Wow, when I started typing no else had replied. I must have slow fingers!

Let me be the first to welcome you to The Stovebolt Page!

Pulling that 12,000 pound trailer seems like a pretty important piece to think about as you make a plan.

A trailer that big probably has its own brakes, but if it were me, I'd start by making sure I could stop this thing quickly in an emergency, even if the trailer brakes failed.

So if you start with the brakes you'll probably conclude that the original axles make fitting adequate brakes difficult. And don't forget that a heavier wheel and tire combination impacts the brakes too, running duals will mean you need bigger brakes...

With that heavy a trailer you probably want to stay with a full-floating rear, so you may want to look at some newer rears under 3/4- or 1-ton trucks all ready equiped for duals (its going to be too wide).

The next question is where are you going to pull that trailer, and how fast do you want to move it? A big six with the right gearing will move that trailer, but might not do so at an acceptable speed.

The diesel might be the best idea, but not my preference.

I've been thinking about these issues for a long time. I'm planning to build one of my trucks to pull a trailer with a truck loaded on it. I'm probably looking at half the weight you are, but have decided to power mine with a 454 and use brakes and suspension from a modern 3/4-ton.

I know of at least one guy who has built a truck to manage a big trailer. I'd love to hear from others who have done this, because I want the best information I can get before I start on mine!