What would be the best way to move a rear axle back about 10"? Would a spring swap be enough, or should the spring attachment points be relocated on the frame? One expensive way I suppose would be to extend the whole frame from in front of the axle; are there any meaningful advantages doing it that way vs. messing with the springs?

I'm trying to decide between a 1st and 3rd gen for a camper project, where I want a bit more room in front of the rear axle than a stock 1st-gen longbed has.

 

You do know how much work your getting into ??

Not knowing your skills but to me the easiest for me would be to just stretch the frame.

Then you only have to get a new drive shaft figured out just how you are going to do that . Might need to relocate the center bearing.

The brake lines will also need to be redone.Lights but you are no doubt going with a custom bed anyway.

I am curious just why do you need the extra 10" and is it worth all the time and trouble

 

Well, no, that's why I'm asking I don't have a lot of fabrication skills. I can drill new attachment points for the shackles, brakelines and light wiring are trivial, but I wouldn't trust myself to weld a frame extension. A new driveshaft is a given no matter how I do it, and that's to be outsourced.

The reason is that I'd like to be able to fit a woodstove right in front of the axle, and a door in front of that, right behind the cab.

 

Yup. You should look into replacing springs anyway... sounds like youll be putting alot of weight on this truck.

 

I figure a 79-85 will weigh 4000 pounds empty and 4500 with all my stuff in it. I will definitely be replacing 25+ year old springs with uprated ones. What's the most I can move the axle just with a spring swap, though? Suppose I find a set of springs with the right overall length and rate, that are really assymetrical and put the axle almost at the rear attachment point; what are the implications for how it'll drive?

Stretching the frame is definitely the most straightforward way, but I can't do it myself, and from what I've been reading it can cost over a thousand bucks.

 

I think doing it like that would result in really bad handling of the vehicle .

Having never done anything like It is only a common sense guess .

If you have a local spring shop maybe they could make a leaf pack that will work for what you want. To be truthful not many of the old custom spring places are around .

No matter how you do this done correct it will not be cheap.

I also think 500pounds of gear is way on the light side it adds up real quick

 

so with this relocated rear axle you are going to do the body work to move the wheel wells back?
look at the curvature of the frame..you will need to do a bit of fab work to make this work...

i would just find something along these lines:

 

Custom work comes with a custom price. Gotta pay to play.

Swapping leaf spring will get you 1 or 2 inches but not anywhere the 10 your looking for.

Maybe you should get a old toyota uhaul truck and convert it to 4wd. Its already long with 1 ton springs in them.

What every you do, its going to cost you. Start saving now buddy.

 

I'm going to build my own enclosure, mostly out of wood, ditching the bed altogether. I wanted to get the axle relocation done first, so yes to your question.

Nah, I'd rather build it myself. Stuff like this isn't so easy to find even in 2WD.

I thought about that, but from what I've read, the frames are much stronger on 4WD than 2WD (at least the usual half-tons). To bring them up to the same spec would be a lot of welding reinforcements. I've heard the 2WD ones aren't even fully boxed?

Huh. I just stumbled upon this - http://littlekeylime.com/MrN/mrnimages/leaf_springs.png If the info on the bottom left is correct... can I just flip the rear springs front to back and gain 6" of wheelbase? (plus driveshaft, shock mounting bar, and brakelines, of course)