Offroad trailer build on 40's.

I have been lurking on here for quite a while, but now I am ready to final build a trailer. I am not really sure what you would call it other than multipurpose. I plan on using it for the following; Offroad camping, hauling crap to my cabin, and hauling luggage out of town to go Jeepin. It will spend a lot of time on the road between trails and will be used for longer offroad expeditions.

I have spent way too many hours searching this forum and there are some really impressive builds.I have 5 kids, so I cannot fit anything else in my Jeep at this point. My Jeep is a 2007 JKU with 1 ton axles, lockers, 40”tires, and a 430hp LS3 I put in two years ago.

The generic outline of the building is going to be as follows:

8x6.5 wheels
40” tires to match my Jeep
Timbren axles
Receiver tube all the way from front to back to allow towing through trailer
Lid on hydraulics with rack on it.
Removable rack above the lid

I intend to do the frame something like this


I expect it to turn out looking something like this.


In reviewing everything on here I have a few questions for some of the builders. In looking at some of the builds, the trailers seem way overbuilt. Some of these have to weigh ridiculous amounts.

1. Did you overbuild, ie tube size?
2. Why rooftop tents, other than cool factor? They are way bigger and more expensive than a tent on the ground?
3. What would you have done differently?
4. Would you have kept it simpler?

I don't want to waste a year building something that turn out to be overbuilt. I want lockable storage to go offroad with some racks to strap stuff to. Any builds I might not have found that I should look at?
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I think the issue of "overbuilding" is that I would say that the large majority of us are just amateur fabricators, and probably most are just afraid to underbuild. We're not engineers, we don't know the structural limits of the material, and say, even the confidence in our welds, and would rather not find out the hard way, like having the trailer break on the road while on a trip, or break while using it. An RTT rack breaking while you're sleeping on it can't be fun . Trying to fix a weak point is usually very time consuming, and can even cause a whole redesign/rebuild, which is money wasted.
I use an RTT for the ease of setup (especially at night and in the rain) and the waterproofness of it compared to a regular tent, and WAY more solid. We've been fine in many heavy wind storms that had destroyed neighbours/friends tents. I find it way more comfortable then a regular tent, and we've found it much warmer. We used it to sleep at a friends house for a party, while my girlfriends sister and her boyfriend slept in a regular tent on the ground. They found it cold even though they had an extension from the house to run a ceramic heater, and he had a toque on. Us, we use just regular bed sheets, had the 12v fan running cause we found it a little too warm.
Trailer frame is 2x4 1/8". RTT rack is all 2x2 1/8. In terms of being overbuild, I could of went thinner I've been told.
What would I of done differently? One thing I didn't see so much was my design being a tad too rear-heavy. I think it's more on how I put it together, cause it's not done and much of the work I did at the start was rearward, but last year I worked up forward of the axle and that rectified the issue, but I can't still put my spare tire on the rear of the trailer at this point; it's just too much weight too far behind, and it also means that I can't do a custom steel bumper like I wanted to cause that will just add more weight in the back.
I've thought about the teardrop style trailer, but it would make it significantly larger I think, and I also don't like the idea of having the bed as the storage area. Putting dirty storages boxes in, or wood, or the bugs from the wood that get into the bed, no thanks. Ya you could put a basket up front, but that would make it even LONGER. The day I have kids, I have a plan to maybe go that route, but at the moment, I love what I got.
So far I wouldn't do anything different except. I love my trailer, she performs great on road and for the light trails and rough roads she's done, she handles it like a dream. For the ease of use and the comforts included it's working out exactly as planned and I truly enjoy it. I just wish I was able to do more myself. A few things I paid to get done because of the concern for safety and the lack of experience in welding/fabrications, but that's more in terms of money spent rather then design changes.
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I finally got the new wheels back today, and just ordered the Timbren axles. It is the same wheels as on my Jeep so that I can have spares. I probably wont start building until September, because it is so hot right now. I am planning on being done in time to take it to Easter Jeep Safari March 2018 in Moab, and hopefully a few runs prior to that. Here is what will be towing it. There is no storage in the Jeep, as I added in a third row of seating.


So all the axles and brakes came in last week. That and I got the tailgate I will be using.


My helper posing as well.

I must say that those Timbren axles are massive and stout.
It is nice enough to be in the garage so I went and bought all the steel. I didn't realize how heavy that receiver tube really is and I am rethinking running it the whole way. I probably still will. The main frame will be 1.5 x 3 inch, 1/8 wall.


I also put together one of the Timbren axles, and then realized I would need a spacer as the axle was hitting the tire. These things are ridiculously beefy. I didn't put the brakes on yet as I will wait until it is mounted to do that.



Expedition Leader
Take a look at an actual M416, which many off-road trailers are modeled after. They are decades old and usually have only given up the ghost because a) some civilian didn't take care of it and it rotted away or, b) somebody physically destroyed it by dropping it out of a plane sans chute or smashing it up due to poor automotive skills.

The frames on those are open channel, .120 at best and likely less. They weigh about 550 lbs rolling and will haul 50% more than their weight on the highway, same as their weight off-road.

Yes, most people massively over build their trailers and pay that penalty in rolling weight, with little real gain to offset it. How much stuff do you really need to haul anyway? I've hauled tents, generators, spare tires, coolers, food, blah blah and don't think I've even come close to cracking 500# of junk.
I started actually building the frame today and got further than I figured I would. I took a lot of time making sure everything was exactly square. It is turning out pretty good. The only hiccup was realizing that I couldn't extend the receive tube through the rear bumper. I am using a CJ7 tailgate and it would hit. I am glad I figured that out now.
Building your own camp trailer is definatly exciting endever. I must say if I would do anything differant on mine is I would go with timberin axles as you are doing. I'm going with leaf springs as I got the axles so cheap. But since it will be used on wash board and 4x4 roads. I wished Did not spend $$$$ on the springs and just went with Timberon instead (I can still change it later)

I was worried about it being tongue heavy but I will be building a bumper w/ double swing outs for the spare tire and small propain bottle and water can. I think when you get rolling you will modify several things, great start I'm looking forward to following along!
I made a lot of progress this weekend. I finished the base frame, and got the axles mounted. I did all the finish welding on the bottom and flipped it over, which was no easy feet.


This is some shots of the front part of the frame.

I welded the Timbren's in after getting the measurements right.

Here is how the tailgate is going to look.

My new Jack also arrived today.



So I finished the cross pieces and welding the top.

I decided to start on the tailgate. I am using a CJ7 tailgate but wanted it to lock. So I bought some "bear claw" latches and a T-handle and cut the tailgate apart. After screwing with it for a while, I welded them in and it came out pretty nice. I will finish welding the parts back together tomorrow but it all works great.




Finished welding up the tailgate today, and started on the uprights.


I decided to mount the hubs as it was getting a little heavy and I figured it was time to put it on its wheels.