I’ am getting a steel flatbed for my truck that’s 10' long. My plan is to cut it off at 8' or 9' not sure yet and make it dump. The only thing I’ am not sure of is how to make the rear pivot without making a complete sub frame and not using a scissor lift. I’ am going to use twin pistons to lift it. I saw a truck like this before the bed set on the arch in the frame and the front and back set on steel square stock but I cant remember how the rear pivot was set up. I was thinking of boxing the end of the frame and putting a piece of 1/2'' plate sticking up on the inside and outside of the frame and putting a pin threw the frame rail of the flat bed. How would this work? Does anyone have any pictures of how one is set up? I wasn’t sure were to post this so I posted under the form that covered my truck. Thanks

 

ive been considering doing the same with mine ...ive thought of using pipe nipples (2" inside of 2 1/2") as my pivot but im not sure how this would work or how long it would last.
im glad you asked the question, it will be interetnig to see what others think or have done

 

I bought a subframe with all the pump and cylinder attached to the subframe.
To set the subframe on the truck frame I used 2" x 4" channel that was adjusted for height with a grinder to make the fit perfect. The two on the front are also long so I could hang under bed tool boxes on them, the bed goes up but the tool boxes stay down.

I do haul a lot more than most people would, and I like the subframe because it helps distribute the load across the frame better. I am running a 9 foot bed, the pivot is about 6" behind the end of the stock frame. Running a bed that long puts the rear wheels almost in the center of the bed, so you have to watch how you load it when you are hauling heavy stuff like concrete or rock. To much weight behind the axle is a problem when you drive.



You can see the two channels sticking out that I mounted the tool box on, this was before I installed the passenger side box.

If you look at my gallery, the first picture is of the other side with the bed down and the box mounted.

Also if you have a bed with the rear apron like mine, if you have too much bed behind the frame watch to make sure you have clearance to the trailer hitch.
I have a pintle hook insert that is rather tall, I can not dump my bed with that insert in my hitch.

 

Dave thanks for the reply that looks like what I want to do. I was going to set mine down on the arch of the frame but did some measuring today and that is going to make it sit to low. I thought the rail on the bed was 6'' tall put its only 4'' and I want some extra room for bigger tires. So I'll do what you did with the 2x4. Is your bed the same width of your frame or is it meant for a dually frame? Mines meant for a dually but I was thinking of widening it. I thought about the apron to I might cut it just outside the frame and angle the corners and take the section between the frame rails out except enough for 3 round lights and close the and of the truck frame and hang my plate there. That will take care of any clearance issues. If its not to much trouble could you take a picture of you rear pivot point and post it I would really appreciate it. Thanks
Also you have one sweet truck, really like the stacks!

 

sorry to hijack, i just have a quick question for Dave......how do you have you exhaust stacks secured, so they dont move this way and that......

 

Actually if the bed frame is 34" wide it was made for a cab and chassis truck.
Dually and trucks that left the factory with a bed installed all have 37.5" frame rails.

My hoist subframe and bed frame rails were 34" wide, the channel keeps it all supported and secured though.
No problems hauling 9700 pounds if it is loaded right, but I do have several other mods like springs and brakes.

The subframe/hoist I bought was made by Rugby, it is electric over hydraulic and rated at 7 tons dump in 30 seconds.

Also I installed F350 4" spring blocks on the rear axle, with the subframe and flatbed combination I can back into a standard truck dock and the truck bed is level with the dock.

Stacks are supported by sky hook duals, model 425 series 2.
LMAO I had to do that.


Actually they are supported by two small brackets welded to the channel turned on edge at the front of the subframe that also is the front tool box support.
I left the downpipe to tail pipe clamp a little loose so the torque twist could make the joint slip instead of breaking the welds on the pipe or pipe if it were welded.
So far no problems in over 6 years of hard use.
All connections other than the downpipe to tail pipe are welded though.

My neighbor has a muffler shop, he had installed a set of stacks on another truck before he did mine.
I told him how I wanted them with no connection to the truck cab and he swore I would be back with broken pipes in less than a month. The other truck he did had brackets at the top of the bed to the stacks and was always breaking the pipe welds.
He can't believe mine are still on and not cracked after all this time.
But since my bed dumps, that connection was not an option for me anyway.

It is pouring the rain down here, if it lets up tomorrow I will take a couple pictures for both of you to look at.
Rear of the subframe for DMAN, stacks mounting point and custom fabricated Y pipe for DNewton.

 

I was just looking at a friend's flatbed dump he had put on his 88 F350. He had it installed years ago at a truck bed place. They mounted it pretty low on the frame, no sub frame. They used the old dump truck method of hinging it. They cut two square notches out on the end of the frame at the top and welded a piece of angle iron that goes across the frame to box it in. Then they just made the hinges out of flat stock and drilled them for pins. I put a single 4 inch stack on it years ago. Now he wants two 5 inch stacks! I'm not looking forward to this one. Next time he comes by I'll try to get a couple pics of how they did it.

 

thanks Dave, id appreciate some pictures........

 

Thanks Dave I would really like to see the pics. I should have my bed home next weekend then as soon as warm weather hits it will be on. I hear ya on the rain it rained here last night then turned to ice. Now after 42 out today and snow melt everything is a muddy mess.

 

I'll try to get some pictures tomorrow of how i built my dump bed. I used some 1" holes in the back of the frame as a hinge point. I reinforced them to keep the hinge pins from tearing out under the stress of the hydraulic force. The pins I made out of 1" hydraulic rod. It'll handle 4000lbs. well enough. That is all the single 4" cylinder I used can seem to handle.

 

Well bad news, I did not get to take the pictures today even though it was nice out.
I am leaving town at 5 AM and will not be back till Thursday.
I will try to get them up Thursday night again.

 

Left click on Jonboy and then click on view gallery, and you can check out how I built my dump bed. It doesn't have a sub frame, only a dump frame that moves with the bed. I made a tie down system, similar to a load binder that I use to lash down the front of the bed when I am not using the dump much, or any time I am towing. It makes the frame much more ridged than a stock bed would be and it gets rid of the clunking that you often hear with a mason dump from the rear of the frame twisting on uneven terrain.
I tried to add the pictures here on the reply, but couldn't figure out how.

 

Jonboy thanks for the pics. When I went and measured the bed the other day I looked at the wrong one the one I’ am getting is 9' something I didn't have a tap with me that time and it has a much taller frame rail looks like 8'' but its still off a 34 inch frame so I will probably widen it to fit mine. With the taller frame rail I may be able to set it on the frame like I planned and use the last few inches of the truck frame to make the pivot. Dave look forward to seeing your pics.