Fabricating dump hoist for my 3/4 ton pickup

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Hi All:If you've tried this before I WANT TO HEAR FROM YOU!! Anybody who's done this or tried it, please chime in! I want all information before taking a torch to a perfectly good pickup!I want to convert my 1989 F250 fleetside 8ft bed into a dump bed. I want to do this using the factory fleetside bed(not flatbed or other). I want to make it in such a way that the truck bed sits just as it would without the hoist under it. that the truck's ability to dump would be "invisible" if you will.I realize a 3/4 ton truck is exceedingly light duty for a dump bed; there are several reasons I want to proceed with this truck.1. I have it; while the truck is a wood hauler, it's in really good shape, less than 100k miles, and the purchase price(from a friend) is $500. I haven't been able to find a trailer for that price.2. The truck's got the lariat package with a/c and cruise so it will be comfortable to drive the hour and a half or so to my parents house for potential work; as well as drive to the reservation where I get firewood from time to time.3. I realize my tare capacity is going to be around a thousand pounds; that's ok with me.4. The log splitter is equipped with a 12v clutch driven hydraulic pump which will work well mounted in the engine compartment and running off the engine.Lastly...well, I just want to do it; with the stuff I have with the truck I have.My Current PlanFabricate a post hoist dump bed using the original factory bed and hydraulic materials from an old log splitter. The hydraulic pump is a clutch driven pump 3k psi pump that I intend to mount on the engine using a modified power steering pump mount bracket. The cylinder is 3", and has about a 32" throw in and out, and it's a 2 way cylinder.Because of the short throw of the cylinder and my desire to do a post hoist rather than a scissor hoist, I'm going to cut 16" off the back of the frame. I'll then fab in the hing pin corresponding distance from the end of the bed, effectively making the bed cantilevered 16" or so. This cantilever will cause the tailgate to nearly touch the ground when the truck is loaded and dumping, but will allow the shorter ram to lift the bed to 50 degrees or so.(with a rear mounted cylinder I may want the hing farther back?)The frame rails which will support the bed are going to be 1/4X3 angle iron; and they are going to be fabbed to the outside of the pickup frame. This is the only way to get the factory bed to retain its factory look and position on the truck.Questions for the Forum:I'd really like to mount the ram to the rear of the truck; in other words, the ram base will be mounted 16" or so in front of the hinges.  The smaller commercial dump trailers employ this design.  This design would allow me to put ALL the stress and force of the hydraulics on the fabricated sub frame rather than on the pickup frame itself.  From what I've gleaned, this design allows for more dumping force...but it looks weak to me.  Thoughts?My projected start angle, whether front or rear mounted is going to be 10 degrees.  Will this be enough?Will the bed clear the cab when dumping?Ideas about mounting the bumper?What have I not yet considered?Thanks in advance for your reading and contributions!!
Reply:"it's a 2 way cylinder"All hydraulic cylinders are 2 way cylinders.They move out and in, or in and out.The phrase you want here is "double acting".Single acting cylinders only operate under hydraulic power in 1 direction, gravity or some other force/energy causes them to return to their at rest position.Double acting cylinders (log splitter, etc.) move in both directions using hydraulic power.
Reply:I would study a scissor hoist setup on an agricultural flat bed dump. That way you could pivot on the rear of the frame without cutting the truck frame. There are several outfits building dump conversions for pickups. I would at least use their brochures to get some ideas.
Reply:Originally Posted by walkerweld"it's a 2 way cylinder"All hydraulic cylinders are 2 way cylinders.They move out and in, or in and out.The phrase you want here is "double acting".Single acting cylinders only operate under hydraulic power in 1 direction, gravity or some other force/energy causes them to return to their at rest position.Double acting cylinders (log splitter, etc.) move in both directions using hydraulic power.
Reply:The rational behind using a scissors configuration is that EVERYTHING about it lies relatively horizontal when the bed is not raised.That means you do not need to orient the cylinder in a vertical direction (post lift) to get it to lift upward.Having to orient a long cylinder vertically means you will need a way to stand the cylinder up and connect to a point on the truck frame and a point on the bed at least 32 inches apart.  To do that, you would need to fabricate some type of tall box frame into the bed for the cylinder to operate in.A scissors type lift can eliminate the need for the box housing by keeping the cylinder orient flat/horizontal when the bed is down.When you are searching for the word to describe what you mean by "long through", the word is "stroke".  The stroke of the cylinder is how far the cylinder moves from completely retracted to completely extended.
Reply:I don't see this working well at all.Frankly, I don't think it's going to be worth the effort for only 1000 lbs or so.What the hell is "tare capacity"?  Do you mean payload rating?  If so, look for a different truck.  My 3/4 ton chevy is rated for something like 4200 lbs payload.My name's not Jim....
Reply:Originally Posted by BoostinjdmI don't see this working well at all.Frankly, I don't think it's going to be worth the effort for only 1000 lbs or so.What the hell is "tare capacity"?  Do you mean payload rating?  If so, look for a different truck.  My 3/4 ton chevy is rated for something like 4200 lbs payload.
Reply:X2. A 32" stroke is long for an 8ft. bed. A 45 or 50 degree angle will dump wood well. Originally Posted by 12V71I would study a scissor hoist setup on an agricultural flat bed dump. That way you could pivot on the rear of the frame without cutting the truck frame. There are several outfits building dump conversions for pickups. I would at least use their brochures to get some ideas.
Reply:If you are dead set on doing a post lift configuration, go study some large dump truck beds.You will then see why that type lift is usually found only on truck beds that actually have enough room withing the cube dimensions of the bed to accommodate a large post lift cylinder set up.And also be aware that the cylinders on those large dump trucks are multi stage rams that telescope within themselves to achieve the extreme stroke necessary to raise the bed high enough to empty quickly/completely.You may not hear from anybody that has done a post lift like you envision.Try to do some math on how much angle your 32" stroke cylinder will impart to the bed when raised to its full extended length.As to one of your original questions about the bed clearing the cab:  If the bed is not touching the cab now, it will not touch it when raising.  As soon as the bed begins to lift, the front of the bed will begin to get farther away from the cab.  The closest to the cab the bed can be is when the bed is completely lowered.
Reply:Originally Posted by BoostinjdmI don't see this working well at all.Frankly, I don't think it's going to be worth the effort for only 1000 lbs or so.What the hell is "tare capacity"?  Do you mean payload rating?  If so, look for a different truck.  My 3/4 ton chevy is rated for something like 4200 lbs payload.
Reply:Originally Posted by FarmerboyGross weight (the total weight) = Net weight (the weight of the goods) + Tare weight (the weight of the empty container).http://en.wikipedia.org/wiki/Tare_weight
Reply:there is a ton of kits available and probably plans for sale also, google what you're looking for, pictures are thousand words  good luck
Reply:1 buy ez dumper type bed insert2 sit in truck3 bolt down4 hook up battery5 done and then you actually have something
Reply:Having done 2 dump beds already and re-doing a third for a buddy  of mine. The beds I did were flat beds that I made. I did this because Ford and Chevy still are putting foam in between the pinch welds in the rear wheel wells. Look at any truck from the salt belt area and you will see what I mean. Anyway, to the OP: You do not have enough room to put a non scissor system in your truck. You would have to make a mount for the bottom eye-lit of the piston that maybe hangs out near the transmission cross member. Also you did not state what fuel tank set up you have but this will also require a lot of modification if things are in the way as well as exhaust modifications. If you put the piston at more horizontal it will want to push and want act as a crusher instead of lifting it. Also I think you are going to add stiffeners (kind of a sub frame) to the factory bed, because if you do not this thing will want to twist every which way when there is a load on it and  you attempt to dump it.Get a scissor assembly and be done with it and adapt your pump set up, build your own hinges too. Not fond of belt driven pump set ups (coming from someone who has used one in plowing for years) because they are slow. Also if you have a double acting set up it will be even slower (power up power down), I go to the local dump every week and there are guys who have this set up. By the time he is done I am already at Dunkin Donuts getting coffee while he is still lowering his bed. I have gravity down with an adjustable control knob in line so I can set the speed of the gravity down speed. I speed it up a little in the winter cause the fluid is cold, then turn it down a little when the weather gets warmer so it does not come down really really fast. I also have my pump set up mounted in a side lower tool box to keep it away from the elements and a key fob remote set up too.If I was to build another dump bed set up I would build my own scissor. The scissor kit I got when I did my last project had to be modified so much I had to cut and add stuff everywhere, and to make matters worse the manufacturer said it was for my truck  I had to modify the skid plate, fuel tank mounts and make the location of the cylinder mount on the truck side 5” up and 3” back, otherwise the scissor would have hit my fuel tank. If you want to see my build, again, I did flat beds, you can see it on my YT channel. Username: tjsnordic.  Also note, your truck will never carry what these things can lift anyway.www.tjsperformance.comDynasty 300 DXHTP 240HTP Microcut 380Hyperthem 85JD2 Hyd Bender and HF Hyd Ring Roller all in one =(Frankenbender)Bpt. Mill/DRO4' x 8' CNC Plasma TableInstagram: tjsperformanceYT: TJS Welding and Fabrication
Reply:1500lbs equals 3 22" diameter blocks 22" long in 2 rows at 50 lbs each equals 30 blocks total.By rough figures, you'll get 24 blocks in, probably 20 or 22(?) then need to start a 3rd row.Not taking into account for fenderwells, plus bark on bark doesn't slide real well.Doesn't seem like much wood to collect for a 3hour round trip drive to and from Parents house.I would rather have the extra 1000 lbs of capacity that lose it to a hydraulic system.