View Full Version : Designing a Trailer

04-04-2011, 07:06 PM
Hey guys...

So, I got this old truck last fall for next to nothing. Its an s10, with 324,000 miles. Its pretty much done for. I made a few videos with it,
before one of my friends destroyed the clutch in it.

The body is really beat up, the inside is a wreck, and its not drivable. I don't think its worth fixing up. If i did, i highly doubt I could get
my $500 out of it.


Anyway, instead of spending my (or his, rather) clutch money on a clutch, I'd rather keep it, sell some parts, and scrap the rest,
excluding the back half, and the frame. Its a Florida truck, and the frame is solid. As is the bed, its rusted through along the wheel
well on one side, but is otherwise good as new. Beat and dented to hell, yes, having a questionable integrity, no.

I could really use a good trailer, and this is cheaper than building one from scratch, or buying one. I need some way to move
scrap without feeling guilty about using my beautiful good truck.

But, I've never built a trailer before.

I trust my welds, I can pass a bend test on an open root weld in or out of position, and I'd feel completely safe following this
thing down the highway. I feel most confident in my smaw welds, so I'd defiantly "stick" with that.

I've never designed something like this, so I thought I'd share my plans. About a foot in front of the bed (I might want to add a
toolbox), I'd bolt a crossmember (see picture), and directly in front of that, and then notch the top and bottom of the "C" frame.
I'd then heat it up and bend it inwards, and then tack everything into position, and start welding.

For the added support piece, I'd weld the big "T" joint, and where the ends meet the pates at the ends, with a 1/8" 6010 root
pass, and then do two weave beads over it with 1/8" 7018. For the top, I'd run the same root pass, and cover it in a weave,
and on the bottom, same root, but with stringers. Crossmember would be made out of rectangular tubing, 3/16" thick.

Or, I guess I could leave a gap and do it all open root. I think thats the way to go here.

And for the frame; thats not very thick, so I'd probably leave a tiny opening (<1/16), and run stringers over it with 3/32 7018, on
both the top, and the bottom.



I just want to know what yall think of this. I know I can do the welds, its mostly the design and the choice of what welds to do that
I'm not sure about. And any feedback would be great. Its supposedly not very hard to register a trailer here in ohio (especially one
under 2,000 lbs), but I'll defiantly look into that more before I start ordering steel, and sawing my truck in half. And yes, I do have a
title for this truck, if that makes a difference.

04-04-2011, 07:34 PM
I just want to know what yall think of this. I know I can do the welds, its mostly the design and the choice of what welds to do that
I'm not sure about. And any feedback would be great. Its supposedly not very hard to register a trailer here in ohio (especially one
under 2,000 lbs), but I'll defiantly look into that more before I start ordering steel, and sawing my truck in half. And yes, I do have a
title for this truck, if that makes a difference.

You would definately need a title for the donor in Pa. They are trying to cut down on stolen parts as well as making sure they get any tax that they might have coming on cash parts (you have to send in copies of all reciepts for all parts showing tax paid).

A few general thoughts beyond the cautions about your welds being good enough and designing with in your limits. ( If you can pass 3g and 4g bends consistantly I'd say thats reasonable) I doubt you'll be under 2K in weight.(I'd bet your empty weight pushed 1K when done) 3-5K gross would be more reasonable with bodyframe and wheels plus a moderate payload. I don't know what the rating is on the rear axle of an S10, but my F250 diesel 4x4 is rated at 6K IIRC and it's a much stouter frame/axle than what you have, so I'd lean closer to the 3K gross than 5K unless you can find specs on that axle.

In most states you will need brakes on the trailer at that weight range. I've never liked hydraulic brake actuators on trailers, at least those with any weight (7K+). On a "light" truck they tend to be a bit pushy compared to electrics in my experience. Keep brakes in mind when doing the conversion. It will suck if you go to register the trailer and find you are over weight for no brakes, or worse yet register it lite to dodge the brake issue and then get stopped going into the dump and they weigh you and find the trailer is over weight for the tags ( BIG fine).

Generally I don't find much to like about converted truckbed trailers. Generally they are too high compared to most trailers making loading a PITA especially if you want to use ramps, they lack decent tie down points for secureing items, look redneck and unprofessional and are usually very small compared to even most small landscape trailers. Cheap might be the only up side, but I've often seen guys spend almost as much as a good commercial trailer by the time they get it all fixed "just right"..

04-04-2011, 07:59 PM
Alright, thanks for the input. A 1991 shortbed s10 is supposed to weigh 2648 lbs dripping wet, and these things are like tin cans in back. But even if it were evenly balanced, thats ~1300 lbs on each end. 700 lbs in something like that is quite a bit of scrap, and plus, theres a lot of other things that I could remove to lighten it up (brakes, gas tank, exhaust, drive shaft, etc).

I'll look into the brake thing here... If I have to put electronic brakes on it, I'm assuming that i'd need a real trailer axle, and that would be a deal-breaker... I'd just go a step further, and build a bigger trailer, from the ground up.

And they're defiantly not the classiest rigs out there, but I see nothing wrong with hauling scrap with one. Generally, I don't get that many looks cruising down the back roads with old farm junk anyway, and with a paint job (I'd take everything apart and sandblast, if its worth doing, its worth doing right), and a $30 used bed liner off of craigslist, it shouldn't be that bad. And with the weight thing in mind, I'd defiantly scrap the tool box idea. That gives me a foot less of frame weight, plus a few hundred pounds from not having a tool box, or the tools within.

But the positives. This thing is wayyy lower than the tailgate of my Silverado, plus, i can drop things into it without fear of dents, move old fence/sheet metal/etc without worrying about the paint. And, I can just unhook the trailer if I decide to wait a little while to go somewhere with stuff. No more driving around loaded down with stuff...

And lets see here...

P.O.S S10 -$500
Clutch money -$400
2.8 v6 (sold for dirt cheap, parts, etc) -$300
Transmission (same as above) -$225
Scrap, from front half of truck -$100
Various other parts, sold on craigslist, ebay, etc +$100
Two chunks of steel to build support, a few electrodes $0

I'll probably go over budget and end up having money in this thing, but I bet that I can find a lot of uses for it.

04-05-2011, 03:43 AM
Lots of slow moving water under this bridge. :rolleyes:

From a design standpoint (i.e. thumbnail engineering), always keep proper tongue weight. Balanced trailers (those that don't need a tongue jack) are unfit to drive highways, in my opinion.

Pickup beds are usually going to balance with a short tongue like that, bad situation. You can overcome the balancing act with tongue weight,or tongue length. (That toolbox may not be such a bad idea after all.)

The axle; minor headache because of weight and extra spinning parts that need lube and then the brake situation. You need brakes, period. Surge brakes ain't all bad if set up correctly and maintained. Surge disc brakes are awesome. :cool: Honest to goodness trailer parts cost money though. :(

Pickup bed trailers go off-road just fine. :p Any pickup bed accessory bolts right up.

A stretched tongue makes good usable space for things like...toolboxes, portable machines, cylinders, vises, etc., etc. :blush:

Way back when I was a youngin', pop bought an old (circa 1930's) Ford pickup bed trailer that had seen more hard miles before I was born than it liked to let on. That thing has hauled everything we ever asked it to for probably 1/2 a million miles since we got it. Oh, it is still close to death, don't get me wrong! This is no Parade Queen. :D The thing just keeps on truckin' somehow...yeah, I got a soft spot for the little, old Ford. Poor little sucker will prolly outlast me. :jester: