The basis for the GearBox is the common cargo trailer that you see contractors and landscapers use every day. The common sizes are 6 - 7 feet wide by 10-16 feet long and look something like this one:
I had a blast playing with the layout and features of my trailer (more on that in a later post), and like the proverbial kid in a candy store, I kept adding things and my trailer size grew accordingly. I finally came to my senses and re-visited my original specifications (
About) and dialed my design back until I settled on a 7'x 12' single axle trailer. I also considered several options and I'll walk you through the what and why of my choices which ultimately led me to special ordering my trailer from the manufacturer.
Interior Height
Stock trailers come in the 6' tall range although you will occasionally see a "tall model" on a lot that is 6" taller. Most manufacturers will build custom versions in 6" height increments up to 2 feet taller (They'll also custom build shorter ones). I'm a tall guy so I needed to order mine about 6'8 " tall.
Single vs. Dual Axles
Axles come in weight ranges from 2900 lb to 5200lb, single or tandems, and leaf or torsion springs. Tandems give you much more carrying capacity and tow somewhat easier (less wandering), but also adds 300 or so lbs. and $300 or so cost, and lessens the turning radius and overall mobility in tight places. For my intended use, I won't be exceeding 3500 GVW so I don't need tandems.
Torsion vs. Leaf Axles
There's also a torsion axle option which is usually a ~$300 upgrade. They're supposed to have a better ride and require less greasing and maintenance, but honestly, I've towed many trailers and I can't tell the difference. I've heard that torsions really shine on larger, heavier trailers, and that might be true, but I don't think towing or ride is a reason to go to the extra expense of a torsion axle for the GearBox. But I did find another reason you might consider it which I'll cover under Ground Clearance below.
V-Nose or Not
The typical cargo trailer is a box, but you're starting to see more with V-noses on them that add 24"-36" of additional v-shape floor space for around $300 extra. A V-nose does give some more inside liveability and it just “feels” larger. But it does take out the room on the tongue and they can be more difficult to back-up. The extra space is nice for moving around in the trailer, but in my opinion its not worth it to try to mount cabinets or add any fixtures in that odd shaped area.
You'll often see claims that they cut the wind better and give you better gas mileage, but I think that's been pretty well debunked by some smart people. The tow vehicle cuts the wind and creates a negative air pressure area behind it so the V-shape has minimal impact on wind resistance.
I chose not to go with a V-nose because I didn't feel the extra cost for the space was worth it, and I wanted to keep the tongue free for my HVAC unit.
Ground Clearance
I want a little more ground clearance than stock for some light off road ability, and its relatively straightforward to do this with a lift kit. Most manufacturers have an option to add a lift for around $200, and Dexter has kits for their own axles that you can install yourself. These basically raise the deck of the trailer which helps alot, but on a standard axle, you still have that straight axle tube between the wheels and this doesn't help that clearance a bit.
Looking closer at torsion axles, they're basically a rubber band mounted crosswise on the trailer frame and the axles are arms on each end of the band that pivot up and down. The torsion bars are mounted up on the frame of the trailer so you don't have that axle tube to catch on rocks. Some improvement in axle clearance, but no improvement in deck height and probably not worth the $300 or so by itself.
I then learned that the torsion arms can be special ordered with a "downstart", meaning they are angled down instead of level, which raises the profile of the trailer (or you can do the opposite to lower your trailer profile). This puts the trailer deck up 2 inches or so.
When you add this 2-3" more of ground clearance to go with the additional clearance you get by eliminating the axle tube, I was interested. If I special ordered it, it was only $150 more than the $200 leaf spring lift kit so I went with torsion axles with a 22.5 degree downstart.
Aluminum vs. Steel Frame
Standard cargo trailer construction is steel frame, with aluminum skin. An all-aluminum trailer is really nice - they're lighter, and seem to be better built because they're a "premium" product. And they will never rust! The larger the trailer, the more the weight savings matter, but for my size of trailer, it seems like aluminum is only about 250 lbs. lighter and at least $3,000 more expensive. All-Aluminum is really nice, but a conventional trailer meets my weight and GVW requirements so I am sticking with steel.
Insulation
Insulation is absolutely necessary to have a comfortable, energy efficient trailer you can sleep in. The only question is if you order it that way or if you install it yourself. Since I'm special ordering my trailer, I looked at what it costs to have it insulated at the factory and its surprisingly reasonable. In fact, if you have the patience and time to order from the factory, many of the options you'll want to add to a trailer can be installed professionally for not much more than what it will cost you in materials and save you tons of time. But if you're reasonably handy, its not hard to install the insulation yourself and there's many youtube videos that show you how. I chose to order mine with factory insulation on the sides, roof and floor.
Windows
I wanted a nice sized, RV style emergency egress window. Like the insulation, I found that ordering from the factory is very reasonable, and unlike the insulation, installing windows is much harder and involves cutting holes in the trailer, framing in the window, etc. etc. No thanks. I ordered mine from the factory, and they were very accommodating to where I wanted it located. If you are installing one in an existing trailer, you might want to have a mobile RV repair company to do it. They seem to be everywhere and unless you're pretty good at this kind of work, I'd recommend paying someone to do it right.
Rear Doors
This is more personal preference. Barn style doors are easier to open in tight places and would be fine for most of the kind of gear I'm hauling. Ramp doors need space behind you to be able to lower them, and need a spring loaded assist for raising and lowering. Ramps used to cost more, but lately it seems they're so common there's little difference in price. I will occasionally be hauling an off-road motorcycle, so I went with a ramp for ease of loading it.
These are the major things that you need to think about before you decide whether to start with a used trailer, a new one off a lot, or a custom order.
