Hi folks,

I've been looking at these kits that will convert your pickup bed into a dump bed.
Any experience with them? Or has anyone done it from scratch??

Any info is appreciated.

Dave

 

New ones can be had for around a grand. I'm just dieing for one, and I do have occasional use for it, but I just can't part with that $$$$ !

 

Same here. That's more than half what I paid for the truck. I don't need it often and the heaviest thing would be horse manure, so I've been looking at this loadhandler site http://www.loadhandler.com/ and brainstorming. I think I can throw something compareable together. If not, they're not a bank breaker.

Thanks, Dave

 

don't bother. they don't work that good. they only move what is on the floor. anything on the sides falls down onto the floor after you have the tarp past it, and you have to get up there with a shovel to get it out anyway. and you need arms like a gorilla to turn that crank handle to wind up the tarp and off load.

 

That didn't last long!!! Thanks for the tip. Guess I'll do some more headscratching.

Thanks, Dave

 

I've been collecting parts for making my crewcab's bed a dumper, but haven't fabricated anything yet as part of the acquisition included a BBF ZF 5-sp with a hydraulic PTO. Since I haven't finished, or swapped in the 460, I haven't swapped in the transmission yet so there's no point to converting the bed just yet. But, here is how I plan to do it:



I will be replacing two crossmembers of my crewcab's frame with homemade ones. The very back one will have the hinges mounted on it, and one of the intermediate ones will have one end of the hydraulic ram I have mounted on it.

The bed needs a subframe of course, and I plan to build that out of 2" square mild steel tubing with a 0.125" wall. All six bed bolts will go through the bed into the subframe, and in the subframe part the bolt holes will be lined with round mild steel tubing also of a 0.125" wall, welded into the subframe. This will give the square tubing more structural integrity than just putting the bolt through the hollow tubing.

Two hinges at the back, fabricated. Each hinge is three pieces, which are fabricated out of 3/8" plate and a 3/4" ID 0.125" wall tubing. Two per side mount on the truck frame, and one in the middle mounts to the bed's subframe, and a long grade 8, smooth shank 3/4" bolt goes through all three, so the bolt is in double sheer. A zerk fitting will be installed on each of the three tubings, and when I grease the chassis every oil change I'll also grease these hinges with the same power greaser I use for the rest of the truck. The hinge on the other side will be the same.

The hinge sections that mount to the subframe, need to be mounted on the bottom of the subframe, and the part of the hinges that mount on the truck's new crossmembers, need to mount on the back. It's done this way so that the subframe will lie flat on the truck's frame when in the "drivable" position, and not interfere with anything when tilted up. If done correctly, Mr. Tape Measure says the bed will not only tilt, but move slightly back when dumping, so the contents falling out of the bed will just clear the rear bumper - then I don't have to make the bumper removable or articulated which adds to the complexity. I also considered taking the rear bumper off the truck frame, and making mounts to attach it to the bed's subframe, so it moves with the bed. So I haven't worked through the rear bumper issue entirely, but having the hinges the way I visualize them (and didn't draw them that well), things should clear so I can leave the rear bumper on the frame.

A very good friend of mine has already started making a dumper bed system using my above design as a guide, though he's modified it quite a bit so that the bed slides back about six inches first, THEN tilts - for him that will clear the rear bumper of his chevy dually crewcab even more. I had thought about that originally, but didn't like the complexity. He's also using 3" square tubing for the subframe, because then he can install a 3" body lift under the cab of his truck and the truck will look lifted, and the body and the bed will line up nicely when things are closed. I hadn't thought about that so I guess with my design as-is I'd want to install a 2" body lift on the cab.

I originally wanted to design this so it fits next to the frame rails, either inside or outside. Inside, there's a gas tank in the way and the other cross members of the frame, which I didn't want to hack out for obvious reasons. On the outside of the frame rails, that means I can't have crossmembers in the subframe for the bed, which means the structural integrity of the bed not only has to hold the load, but also hold the two sides of the subframe together. I prefered not to do that as beds age, they rust, and fall apart. Would suck to have the hydraulic ram push through at some point. So on top of the truck's frame made the most sense.

While not a complete design, I drew just enough to trigger what I visualize in my mind when the time comes to make this. Hope my text describes it enough to point you in the right direction.

Absolutely, positively, have the bolts of the hinges in double sheer, and use grade eight bolts, and zerk fittings to grease them every so often.

Oh, and the other neat thing about this design... unbolt the hydraulic ram off the bed's subframe, and pop the two bolts out of the hinges, and the bed's removable. No more dealing with rusty, spinning bed bolts. Bolt the bed to the subframe and don't think about it ever again unless the heads rust off.

 

BTW, as far as cost goes, the hydraulic ram and valve cost me trading an old porsche transmission that I didn't want anymore, that a friend wanted for his dune buggy. I'll have to buy hydraulic lines and make fittings, or possibly buy complete hoses already made depending on cost. If you don't have a PTO on your transmission, you can always drive the hydraulic pump via an electric motor, the way many snow plow systems work. The subframe and hinges I'm fabricating, so the cost on those parts is very low. Certainly in the <$100 price range. The cost will be the PTO, valve, and hydraulic ram.

The next time you pass a new car dealer that has commercial trucks pushed off in the corner, see if they have a dumptruck. Doesn't matter if it's an F350, Chevy 3500, or a Dodge whatever. Even Isuzu flat-nose. Take a look at the angle of the hydraulic ram and how it mounts, take a few pictures with your digital camera or cell phone, and you have the "engineering" done for you. That's all I did.

The complexity in this is the rear bumper possibly being in the way. Commercial dump trucks, even if on a "toy truck" frame like an F350, generally don't have rear bumpers.

 

Frederic, you IS the man!!!! Now I can picture something. I work on a Kassern that was the hub for construction and fabricating in this area and is 75% closed up now. Everything (tons of scrap iron and goodies) is just laying around. I'll look at your stuff and go "shopping" next week.

Thanks again.

 

Frederic, you're a genius!

I saw Stacey on Trucks install an "air" kit on an F-150 4x4 once. Looked neat, but if I remember right, it was over $1k.

Good luck in your search, and your project!

Nightrain

 

Glad you guys like. I'll be making mine even if you didn't ::grin::

The subframe for the bed is important - since the structural integrity of the bed relies on being attached to the frame rails, so you need to build something reasonably substantial if you want the bed not to flop around like a soggy pancake.

I would also recommend building a lock for the front of the subframe, so when the bed is dropped down to it's normal position, it automatically locks. I intended to mention this earlier, but alas I forgot.

I will be using two bearclaw latches, similar to the tailgate latches or the door latches. You can fabricate something like this too:


I offer the above picture to illustrate the idea, obviously you're not going to use a pair of $5 home depot gate latches to hold down a 400-500lb bed. That's asking for serious trouble, but you can make such a thing out of say, 1/2" plate over a grade eight bolt shank welded to the subframe. Be creative!

I think bearclaw latches are the best choice, and there's no shortage of them in junkyards. Just find a big door, or a large tailgate, or something like that.

You can use air bags to actuate the bed instead of the hydraulic cylinder. It's easier to fabricate, easier to plumb, and the pressure is much lower than a hydraulic system, but there is one disadvantage - smoothness of operation. Hydraulic cylinders if sized even remotely correct (meaning you can be way off), will actuate the bed smoothly over a period of time. Meaning, you engage the "tilt" lever/valve the bed will move smooth at "X" degrees per second. With an air bag, it will not move at all while the air bag fills up and expands into the space, then suddenly, will start to lift at an exponential rate, either really fast at the beginning then slow down, or slow at first then suddenly accelerate. If the load is really heavy, and your compressor is fairly small, the bed will bounce or oscillate because air is very compressible - the very principle why air shocks and air springs make great suspensions - they can absorb road irregularities that cause sudden and odd suspension movements. So an airbag will allow the bed to bounce and oscillate if the load is uneven, or very heavy, or your compressor is too small.

Hydraulics basically is a more solid mechanical actuation method, and why it's used in steering and brakes. Move the brake pedal "X" inches down, and you have "Y" amount of braking capability. Push more, have linearly more braking capability for that distance.

What makes installing hydraulics easy in trucks like ours is if you can find a PTO pump to hang off the side of the transmission. Then all you need is a resivior, the direction control valve, and the lines.

The other advantage of hydraulics, is if things don't leak (including the hydraulic cylinder) is if you put the bed 1/2 way up and close the valve, it will stay 1/2 way up until you open the valve again. Air springs/bags, well, as you take the load out of the bed the bed will tilt up more. If you climb in, the bed will move down because you're adding more weight.

There are many good sources for hydraulic rams. If you find a dump truck based on the F350 or F450 platform, you'll find every part you need so leech them all. Rams can be bought from harbour freight and many of the other tool importers as well if you want a shiney new one. Also, bucket loaders, tractors, old tow trucks, fork lifts, pallet movers, etc.

Another option for actuation is to have on the back side of the hinge a protrusion that hangs down, that you attach a pulley to and a cable, and use an under-cab winch to pull that protrusion which will pull the bed around the hinge, thus tilting it. This is probably the easiest way of actuating a dump bed, however I've always been worried about the "what ifs" should the cable snap. Will it fling around and cut off your leg, slice a hole in your gas tanks, cut a brake line, etc. Hydraulics at least if something pops, generally the orifaces in the hoses, fittings, valving and most hydraulic cylinders are small enough that the bed will come down, but not drop like an anvil, even when loaded.

 

Think I'll try the idea out on a trailer first. Timing is everything!!! I just fell into a deal on one with about half again the capacity of the truck and no obstructions (wheel humps). The German police had a truck and trailer stopped at a rest area this morning that was obviuosly overloaded. I stopped to answer my phone and they were argueing back and forth until they started to unload stuff. They'd set something off and the cop would shake his no, and so on. I offered to take the trailer (it was loaded on the bigger one) and got it for about 25 bucks (20 Euro). Your idea will be foolproof (right up my alley) on this. I can pull it with my tractor and operate the hydraulics by adding another joystick and plugging a hose into my tractor and keep the truck pretty and sweet smelling. Save me some weight on the truck too. Because the primary use is for our horses, I can't by gas for it on post like I can for our cars, so pay $6+ a gallon.

Thanks,


Dave

 

I got mine from www.surpluscenter.com but I just looked, and they don't have it listed anymore. It's a 2 ton hoist, supposed to fit all pick-ups from 1970 thru like 1993 or so...though I found the hinges wouldn't fit inside my frame rails, like they were supposed to, so I just welded them on, boxing in the end of the frame.

Anyhow, it came as a complete kit, with an electric pump, and toggle switch for the dash. It cost right around $850. I love it! I've used it quite a bit. Probably not enough to justify the purchase, but after hand unloading a load of plaster and lath, I decided to go for it. I don't think it will actually lift 2 tons, though, and there isn't a subframe for the bed, which means it flexes quite a bit now. But, I rolled onto the scale at the dump a while back, and weighed 11,360lbs, that was concrete. The empty truck, with me in it weighs about 4500lbs. It didn't lift it of course, but the bed handled it alright.

I do have ideas for redoing it myself, but I kind of tend to do more with my truck then most people. But since I fix it myself, I'm also not afraid to break it. One thing I don't like about the hoist, is that when the bed is down, the end of the hoist is only a few inches above the pumpkin. When there is a load on it, the hoist sits on the rear axle. This can't be good.

BTW, it's a 1971 F-250 360 Holley 4bbl 4spd 2WD

I'll take pictures if you'd like.

Brian