The Forestry Forum

General Forestry => General Board => Topic started by: alsayyed on December 28, 2006, 10:46:06 AM

Title: Replacing or converting pick up truck box into flat bed
Post by: alsayyed on December 28, 2006, 10:46:06 AM
Hello to everyone. I need some help in how to fabricate flat bed for my GMC pickup.  I have 4X4 GMC PICKUP K3500 1994 extended cab. I am thinking to remove the cab behind and place flat bed with 12 inch rail on four sides. The reason that I wanted to do that to carry all sorts of things from logs or bricks. Could anybody tell me where to start or have you seen a project been made like the one I am talking about. Dose anybody have seen fabrication plan.


Title: Re: Replacing pick up truck cab with flat bed
Post by: Raider Bill on December 28, 2006, 11:08:40 AM
Are you replacing the rear cab as well as the bed?
Title: Re: Replacing pick up truck cab with flat bed
Post by: Steven A. on December 28, 2006, 11:23:14 AM
When I was going to build one quite a few years ago it was almost as cheap to buy a factory made one if I valued my time at even minimum wage.
I don't know if that still holds true today but its worth checking out.
Mine is on a F-350 Ford and it is waaaaay handier than a regular box.
Title: Re: Replacing pick up truck cab with flat bed
Post by: alsayyed on December 28, 2006, 11:50:28 AM
Yes I want to replace the back box not the cab, I am sorry to mention this. I mean the back box with the tailgate door.
Title: Re: Replacing or converting pick up truck box into flat bed
Post by: gary on December 28, 2006, 06:14:48 PM
If your going to put a wood flat bed on it is easy. use a couple of 4x4s
across the frame and attach your planks to them
Title: Re: Replacing or converting pick up truck box into flat bed
Post by: submarinesailor on December 28, 2006, 06:29:52 PM
That’s how we did it.  A couple of 4x4, one across the front, one across the back – bolted in place.  And the bed running back and forth between them.

Bruce
Title: Re: Replacing or converting pick up truck box into flat bed
Post by: mike_van on December 28, 2006, 07:53:18 PM
I wish i'd taken a pic. of mine, just had it off to de-rust & POR 15 it.  On my F350, it's 9 ft long, there's 2 4" chanell iron that go the length. These line up with the 2 frame rails and are attached with 4 big U-bolts.  Across these, spaced every 2' are 3" I-beam 7footers for the width. The outsides are 4" chanell iron, welded on so that 1 1/2" thick lumber sits down in them, flush with the top. I've had flatbeds since 1974, for me it's the only way to go - (http://www.forestryforum.com/gallery/albums/userpics/11530/ford1xxx.jpg)
Title: Re: Replacing or converting pick up truck box into flat bed
Post by: thecfarm on December 28, 2006, 08:36:38 PM
I had a factory flat bed on my truck.The sides were about 2 feet tall and each section was half the lenght of the body.I could remove each half or both of them.I ran a chain up high on the back and I had two 2"x2" with about 1½" for a gap to put a few inch boards for a tailgate.This made a great work truck.I did add about a foot to the bed.I got tired of shoveling gravel or whatever onto the rear bumper.
Title: Re: Replacing or converting pick up truck box into flat bed
Post by: rebocardo on December 28, 2006, 09:13:46 PM
Okay, hey is what I recommend on building a flatbed.

3" x 3/16" C-channel. Make a square, as wide as the truck, so it sits 2" above the cab installed. Put a center post in the middle of the box. Right below the window weld in cross sections, left to right. So, now you have a box with what looks like a cross in the middle.

On the bottom of the cross install 1/8 thick plate steel on the bed side! Above the cross member at window height install 1" tubing, left to right, spaced with 1-1.5" in between them. Use grade 8 1/4" bolts, do not weld. This will be a removable "headache" rack in case you ever have to replace the back glass.

Over the plate steel install 2" pressure treated wood. This will prevent anything in the bed from coming forward into the cab during an accident. The 1" tubing is good enough for  preventing things such as firewood from killing you in an accident. Obviously willnot stop a 1100 pound log.

Bolt it to the frame with (2) 1/2" grade 8 bolts on each frame flange. You can weld it there too, BUT, use the bolts even if you weld.

Build a box for the back too without the cross, gusset the corners.

Run cross members of 3" x 3/16 on 16" centers from front to back.

Run 3" from the front box to the back box at the top and bottom outsides.

Now, get 1.5 x 1/8 wall, make a roof rack along the outer edge (not middle, you want to stand up) to over the cab. Over the cab run two pieces down the middle of the roof to the  first box.

One of the middle cross members will require a hort. piece of 3/16 as tall as you want the flat bed.

On the inside of the boxes and vertical supports run 2" PT wood. I put the floor on last since you are more likely to replace floor boards. I leave a 1/4" gap for water to drain out at the front and sides.

On my flatbeds I put gates made of 1" tubing with expanded metal grills that can be folded all the way flat against the sides of the bed when open. Reason being is I hate walking into a tailgate that is not folded all the way down.

The roof rack is for carrying ladders and such. I found it is not the ideal spot for drywall on the highway :-D

Also helps when carrying stuff you do not want to tip over (fridges and windows) and still want to tie down securely.

Plus, you can use the top of the front box for off road lights.
 
I suggest a min. of 18" sides so stuff does not bounce out. I go 24" high. When I want to get something out, I climb in. On a lifted truck it discourages causal thieves if the gates are locked.

 
Title: Re: Replacing or converting pick up truck box into flat bed
Post by: Polly on January 25, 2007, 10:03:47 PM
  8)  i seen one advertised in truck trader it looked nice i think 600.00 youcant build one for that unless you got a big metal scrap pile 8)
Title: Re: Replacing or converting pick up truck box into flat bed
Post by: DanG on January 25, 2007, 10:21:50 PM
Truck bed...$600

Shipping to Qatar...Priceless! :o
Title: Re: Replacing or converting pick up truck box into flat bed
Post by: trim4u2nv on January 26, 2007, 01:23:16 AM
Get one from the junkyard if possible.  They are normally  bolted on with large U-Bolts to the frame and easily removed.   In the Chicago area you can pick one up with stakes for around $300 and $500 with a liftgate used.  Then again I don't kwow what is available near you.   You could scarcely buy the steel for those prices.