Building my own trailer - need some advice

[N8TGK]

Sounds like a two axle trailer application to me as well. Also with that much weight, you should be careful of how you position the load on that trailer to keep tongue weight under control. What kind of tow rig are you using?

When I was involved in Dirt car racing, we pulled a 24' race trailer with a crew cab dually with a big block 454. We didn't have a 5th wheel set up so we used load bars on the hook up. It worked, but for that weight it would have been better to be a 5th wheel set up. I think it was a 10,000 lb capacity and it was dual wheeled with dual wheel electric trailer brakes. Those load bars were bent a frightening amount when they were hooked up, but they never broke and helped level out the tongue/hitch connection. My crew chief had done it a million times, so he thought they would hold. It looked like a disaster waiting to happen to me

Why mess with 2 axles instead of 1 big / heavy one? I'm never gonna have more than 8000lbs counting the weight of the trailer itself so why would I go through the added trouble of making 2 axles play nice together when I can buy 1 9000lb axle and call it a day?

Tow rig is gonna be a half ton GMC Sierra 1500 with electric brakes. I'm definitely not gonna even consider messing with a gooseneck / 5th wheel for making my own - I'm nowhere near that good of a welder. I mean it's really unnecessary for that little weight isn't it?

I'm unfamiliar with what you mean by load bars? The extendable poles you use to keep a load from shifting in the back of a truck or enclosed trailer?

 

[N8TGK]

I would Imagine California, another well regulated state, has similar requirements...

Yeah good thing I don't live there either. I'm in Idaho, just didn't want to give my city so I told the site LA lol... There I fixed it... All I need is the trailer, a weight slip, and a superficial "inspection"

 

[sdelivery]

My suggestion is you find a trailer large enough and heavy enough for your intended use and renovate it.
You have the benefit of an ENGINEERED machine, with many of the potential safety concerns as well as liabilities off your plate you can get around to the fun part of upgrading and customizing for your use.

 

[N8TGK]

I think we need more information. A quick check on hydro seeders shows they range in weight from less than 300 lbs. (empty) to over 1,200 lbs. The same is true for a pressure washer. Depending on the size and options they can weigh as little as 150 lbs. or over 550 lbs. The water alone will weigh 5,500 lbs. Don't forget the weight of the totes. They're usually around 150 lbs. each. Add in a small self-powered pump, hoses, nozzles, and accessories and you have another 200 lbs. or so.

Given these approximate weights if you go with middle of the road sizes I would get 2 axles rated at 5,000 lbs. to 5,500 lbs. each. I have a 5'x 10' trailer with Dexter 5,400 lb. axles with electric brakes. I recently replaced the original springs with 5,200 lb. sets from Southwest Spring. They happened to be on sale for $321.00 at the time.

I believe almost all states require brakes, and a break away system for trailers over 3,000 lbs. Most states also require a trailer of that size to be licensed. If its factory built, you'll need to give them the manufacturer name and serial number. If its homemade it will probably have to be inspected before issuing a license.

For fenders I would use 7 ga. diamond plate rather than the cheap sheet metal fenders. My sheet metal fenders rusted though and cracked within the first 5 years I had it. It's nice to be able to walk on the fenders and not have to worry about destroying them.

My trailer frame is made from 4" channel. The tongue and support tubes are 2" x 4" rectangular tube. The weight of the trailer alone is 2,100 lbs. It was originally built by a construction company to haul an 8,000 lb. Bobcat skid steer. Tires and rims are going to be another concern. My trailer uses 15' 6 bolt rims with 225/75R15 load range E tires.

Personally, I would stay away from tube for the trailer frame. I would also leave the ends of the tongue tubes open so they can drain or be washed out. I've seen far too many closed tube trailer frames rust out due to trapped water and mud.

Here are a few pictures of my trailer. It has a wood box installed on it for hauling leaves and trash. The box can easily be removed in sections to haul the tractor or end loader. Loading the tractor or loader requires the ramps which weigh another 120 lbs. each.

I'm in Idaho, just didn't put that on my acc cause it wanted a city, so I put LA since it's the first big city that came to mind. With a trailer that big I *might* need brakes but I don't think so, although I intend on using an axle with electric brakes anyway regardless of whether I actually need it.
IDGAF about a break away system either but that's cheap and easy to add later... All I need to get it road legal is the trailer itself, a weight slip, and a superficial "inspection", and I may not even mess with that since the trailer is gonna spend its whole life in a small rural area with a ton of private roads, but for safety I would like to build it good enough to be road legal.

I like the idea of diamond plate on the fenders, will probably do that. My current trailer has sheet metal fenders but heavy gauge and I stand on them all the time so that's a must for me.

Why would I mess with 2 axles? It seems redundant and a TON of extra work to do 2 when I could do 1 heavy duty / 9000lb one. I mean a 9000lb axle if I never have more than 8000lbs should be fine right? For wheels idk I just kinda figured on using whatever the biggest / easiest to get off the shelf tire is. The only reason I can think of is so it'd be easier to distribute my weight but I'm not convinced it's worth it.

Good point about the square tubing rusting although I was planning on drilling holes for drainage. I live in a very wet area with a ton of salt on the roads so that's even more of a concern here. I figured about the same weight for my trailer as yours at 2000lbs but it would probably end up being a tad less than that. What thickness is the 4" channel on your frame?

Also, nice trailer!

 

[N8TGK]

My suggestion is you find a trailer large enough and heavy enough for your intended use and renovate it.
You have the benefit of an ENGINEERED machine, with many of the potential safety concerns as well as liabilities off your plate you can get around to the fun part of upgrading and customizing for your use.

That's a good idea, but it's also outside my budget, and I'm wanting the challenge of the project. I'm not very good at welding and I figure an excuse to do alot of welding is a good way to fix that.

Also I want the footprint to be VERY small. I'm thinking no bigger than 4x10 for the main bed. Find me a single manufacturer that makes an off the shelf 4x10 utility trailer with 10000lbs worth of axles and I'll give you a crisp high five, I just don't think it exists.

The goal is to be as compact as possible, with the ibc totes stacked over the axle, the hydroseeder behind it, and the pressure washer and water pump in the front.

Besides, anything store bought that big would almost certainly be dual axle, and I'm far from convinced that's necessary, or even desired in my application. I want the shorter wheelbase, and easier maneuvering of 1 axle, plus those axles with electric brakes and good tires are expensive...

 

[Asm109]

You want dual axles at that weight range. Single axle with a flat tire and that weight gets interesting in a jiffy.

You admit you don't have the knowledge to design and size the steel frame of a trailer this size. For that you would need a degree in Mechanical Engineering. You are getting a lot of advice from people who USE trailers in this weight class that you need dual axle.
You are blowing them off because you aren't convinced it's necessary, but you have already told us you don't have the knowledge to make that call.
Buy a good life insurance policy to take care of your loved ones.

 

[N8TGK]

You want dual axles at that weight range. Single axle with a flat tire and that weight gets interesting in a jiffy.

You admit you don't have the knowledge to design and size the steel frame of a trailer this size. For that you would need a degree in Mechanical Engineering. You are getting a lot of advice from people who USE trailers in this weight class that you need dual axle.
You are blowing them off because you aren't convinced it's necessary, but you have already told us you don't have the knowledge to make that call.
Buy a good life insurance policy to take care of your loved ones.

I didn't think of having a flat tire, that could be complicated for sure. But I want the footprint and wheelbase to be quite small, and dual axles would price it too far out of my budget, with a bunch of added maintenance I don't want. Double the brakes, double the tires, double the cost, more than double the work.

The idea here is to build myself a trailer that'll suite my needs, not necessarily one that's perfectly safe in every possible way. Realistically I'll very rarely have both totes full. I want to stack them, I figure the best is to have the bottom one almost always full, and fill the top one only for big jobs when I know in advance I need it. It's not like I'll be maxed out at every moment of every day, it's water afterall.

 

[o0norton0o]

To answer your questions as best as I could, but I'm not an expert so I'm just talking from what I have seen and experienced...

Load bars are these 2 spring steel rods that engage the truck's tow hitch to the trailer tongue. They create a spring effect in the vertical direction so it takes some of the sag out of the hitch/tongue connection and transfers the weight on to the truck's rear suspension and the trailer suspension. It's a way of canceling some of the droop on the hitch due to excessive tongue weight.

I think you are beyond pushing the limit on every aspect. I have a GMC Sierra 1500 myself with heavy duty cooling and the towing package. I wouldn't do any of the things you plan to do. I wouldn't pull 9000lbs with a single axle. I wouldn't pull it with my 1500 sierra. I wouldn't have a heavy trailer with no electric brakes... Clearly, we have different sensibilities, so I'm just going to drop out of this conversation....

Picture of load bars below. Our load bars for our trailer were part of a pintel hitch which clamps down on the trailer's tongue ring and is a heavy duty hitch, unlike a standard ball hitch and jr. high load bars pictured below...

 

[N8TGK]

To answer your questions as best as I could, but I'm not an expert so I'm just talking from what I have seen and experienced...

Load bars are these 2 spring steel rods that engage the truck's tow hitch to the trailer tongue. They create a spring effect in the vertical direction so it takes some of the sag out of the hitch/tongue connection and transfers the weight on to the truck's rear suspension and the trailer suspension. It's a way of canceling some of the droop on the hitch due to excessive tongue weight.

I think you are beyond pushing the limit on every aspect. I have a GMC Sierra 1500 myself with heavy duty cooling and the towing package. I wouldn't do any of the things you plan to do. I wouldn't pull 9000lbs with a single axle. I wouldn't pull it with my 1500 sierra. I wouldn't have a heavy trailer with no electric brakes... Clearly, we have different sensibilities, so I'm just going to drop out of this conversation....

Picture of load bars below. Our load bars for our trailer were part of a pintel hitch which clamps down on the trailer's tongue ring and is a heavy duty hitch, unlike a standard ball hitch and jr. high load bars pictured below...
View attachment 475610

Hmm interesting, seems like a good way to get stuck in dirt and mud.

I've pulled a dump trailer rated for 12000lbs with an unknown but large amount of weight in it and never had any problems. 8000lbs shouldn't be a problem at all for that truck, it's not even double the weight of the truck and well within the stock towing capacity.

How is 8000lbs on a 9000lbs axle pushing the limit? I can see how if I got a blowout it could be bad but even then it shouldn't be the end of the world - absolute worst case scenario what? I dump my load of water on the side of the road and move on with my day.
I said I intend on having electric brakes whether it's required or not so idk where you got that from. No electric brakes would be a death trap...

 

[Firstram]

I didn't think of having a flat tire, that could be complicated for sure. But I want the footprint and wheelbase to be quite small, and dual axles would price it too far out of my budget, with a bunch of added maintenance I don't want. Double the brakes, double the tires, double the cost, more than double the work.

The idea here is to build myself a trailer that'll suite my needs, not necessarily one that's perfectly safe in every possible way. Realistically I'll very rarely have both totes full. I want to stack them, I figure the best is to have the bottom one almost always full, and fill the top one only for big jobs when I know in advance I need it. It's not like I'll be maxed out at every moment of every day, it's water afterall.

Stacked 330 gal IBC totes filled with water on a single axle trailer behind a 1/2 ton truck.


What could go wrong!!