I am in the planning stages for building my truck. 1979 F-150, 2wd but want to build my own frame. I have easy access to tubing, I am a journeyman welder buildng vacuum trucks, so I have the know how as far as building the frame. I am curious as to what drivetrain would be better, leaf springs, any ideas would help. My goal is to run 38 inch tires and 8 inch lift or so. I do want resonable gas mileage, but realize it will not be great. Again, any ideas are appreciated. Also, extended cab 4x4s are rare around here, so that explains the conversion.

 

gas mileage can be good with the right total gears, you get a super over drive 5 or 6 speed you could get ok gas milage. what type of offroading are you goinng to do? what type of ride do you want? a little more info about what your end goal is would help.

 

I am mostly looking for daily driver, but would like to go on some trails. I dont have far to go as far as driving to town or work, but dont want to have to fill up every time drive it. I also want to be able to work on the drivetrain. That means old skool as far as litlle to no computers as I dont want to run to the mechanic if something goes wrong. I would like to completely rebuild everything on my own, Im just not experienced with the computers. I would like to go for fuel injection on the motor as I have researched the self learning kits out there like FAST.

 

leafs are the simplest, or you could get into 4-links with coils and all kind of stuff. depends on how complicated you want to go or how much flex you want. leafs are usually adequate.

 

You have a 2wd truck and want to convert it to a 4wd by building your own tube frame?
Registering the thing would be interesting to say the least, but you must determine how you intend to use the truck. Leafs are cheap and easy to set up, but also require some work to obtain the proper rates and lengths. Shackle angle and the angle of the spring is just as important as the proper angles for a multi link system.
One links and radius type arms are yet another option, and much of this will be determined by the overall fab skills.
Welding the components together is really the small part of taking on a project like this. Bending tubes, keeping the thing square, and consistent from side to side is critical. Some fancy engineering will have to be taken into account, you will have to maintain a certain amount of structural integrity.
Have you determined a particular chassis design yet? You gonna make a complete frame and complete cage to add support? Tube chassis have a tendancy to fold up without placing the right support in the correct places.
The costs associated with this would be pretty high for a daily type driver. I would imagine the thousands of feet of DOM alone would cost much more than a comlete 4x4 truck already built. If the desired truck is not available locally, you could have one shipped for far less than a complete tube truck would run, even if you build it yourself.
Big bucks........Most projects like these never get off the ground, and those that get started usually end up a lost cause after a couple of years. Enthusiastic approaches are great, but the work involved would be staggering.

 

I have priced out 5 x 3 x 1-8 material and it cost around $500.00. The way I figure all I have to do is figure out my body mounts, leaf spring mounts, crossmembers. This is a project that I want to do. I have built subframes for vacuum trucks for 8 years. My boss is an engineer and he has said that he would help me design it. My 2wd was a freebie from my brother and the only other extended cab 4x4 around here is $12,000 with a deck and would still be making changes. I know this is not a simple answer, but what else to do. I did find a 1990 F-250 4x4 extended cab for $300.00. Anybody know about swapping that over. Either way I wanted to get opinions on trannys, transfer cases, axles, which would be better to use. Thanks for the input so far.

 

you want d60 front axle and 10.5in rear for those tires with chromo shafts and lockers and that's about all i know lol

 

I don't think he is talking about DOM but HSS tubing. Very good strength for the amount of material in it, and fairly common in commercial construction. . .and relatively cheap.

Just curious, are you just going to cut and weld the tube together to follow the basic profile of the existing truck frame?

Also, I personally would go with a slightly thicker walled tube. . .maybe 3/16". Just for extra wall strength to prevent anything from punching through. . .but that's just me. . .

Leaf Springs would be the easiest I think to adapt to a custom frame. Dana 60 front for those tires. Dana 70, Sterling 10.25, Dana 80 rear end. . .nothing particularly special. The dana 60 front though, since you are already doing so much custom work, you could probably slip a "newer" 85.5-92.5+ dana 60 in there. . .just widen the frame up front to match the axle. If you do it right, you could use stock 70's f-250 front spring hangers.

If you can convince the DMV up there that the truck is a 70's truck still, then just go with standard 70's motor/tranny/t-case. But, since you are doing this much work, why not swap a mechanical cummins turbo diesel in there

You'll get better than good gas milage, and it would definitely have a wow factor to it

 

regester and insure the truck before you do the mods lol and as far as anyone knows its a stock 70s truck on paperwork

 

I would link the suspension up front and air bag it, firestone bags. It rides nice with the bags. Its cool to have a heavily modified truck but if your gonna do all this work you want it to ride nice also. You can do coilovers but how much do you want to spend is the question when doing coilovers and long travel setups. I run on 40's and dana 60 frt and it rides nice for a big truck. It surprises a lot of people on ride quality and durability. If you do a link suspension make sure your lower arms are dom or cromo incase you drop on a bar it won't bend. I used 1" QA rod ends and never had a problem. Its a little overkill but I don't work on it much these days as far as suspension. My girlfriend likes the air ride because it don't hurt her ***** anymore compared to coils back in the day. Best compliment I ever got on my truck.

 

I would link the suspension up front and air bag it, firestone bags. It rides nice with the bags. Its cool to have a heavily modified truck but if your gonna do all this work you want it to ride nice also. You can do coilovers but how much do you want to spend is the question when doing coilovers and long travel setups. I run on 40's and dana 60 frt and it rides nice for a big truck. It surprises a lot of people on ride quality and durability. If you do a link suspension make sure your lower arms are dom or cromo incase you drop on a bar it won't bend. I used 1" QA rod ends and never had a problem. Its a little overkill but I don't work on it much these days as far as suspension. My girlfriend likes the air ride because it don't hurt her ***** anymore compared to coils back in the day. Best compliment I ever got on my truck.

 

idk why everyone thinks you need a dana 60 i run 44" tsl's on a dana 44 with chrome shafts and ctm u joints i have yet to break one and i am not light on the right foot

 

and i ran 36's with stock shafts for 2 years without a problem i just broke rear driveshafts

 

Exactly what I was thinking.


It seems like the idea for your muli-purpose rig.. would be a little more work than you think.