Tiny Cargo trailer ideas
 

Hi Guys,

Long time lurker, first time poster, excluding my intro post. I have a good sized trailer that is really too big to tow with my wife’s 17 Subaru Forester. We love her car, but sometimes we need to take more with us, when we go camping for example. I have a truck, but we get 30-33 mpg out of the Forester when we are eco friendly drivers. I have a pretty good skill set, and would like to build a small trailer, bigger than a motorcycle trailer, maybe 3x5 platform and 3 foot height inside. That’d give me 45 cubic feet of space.

So, after reading everything I can find on trailer aero, I’m still looking for the best answer in my situation. I’ve read aerohead’s boat tail thread, as well as the one wheel trailer thread, and a few others, as well as what I can find on the net. I know the gap is a good place for reduce aero, but my wife is not going to go for anything crazy there. I can minimize the tongue as much as is practical, and I’m not sure what that length really is. Most people are saying the tongue should be a min of half the cars width. I’ve looked at aero friendly designs like the Airstream Basecamp, and I think I could make a shape like that on a smaller scale if it was appropriate. I should be at least 2 feet under the roof edge of the Forester, so I’m not sure it’s worth it to make a curved front. Although I think that could be as easy as radiusing the corners.

So, what’s the best design for what I need? A mini base camp? Or is a box on wheels that is narrower and shorter than the tow vehicle and in its wake already as aero as it needs to be? I was going to attempt to look at it with the template, but I wasn’t totally sure on placement relative to the tow vehicle and trailer relationship. I was initially thinking a box with the tires inside the body, so essentially skirted, and maybe with a roof that slopes to match the template and a Kamm back on the tail.

Let me know what you all think. Also, if you have experience with small trailers, I’d happily take any opinions on what you’d use... I was initially thinking a single place snowmobile trailer, but I haven’t found one. Boat trailers are abundant, but would require a fair amount of work. I could use one of the Harbor Freight kits also, but opinions seem mixed on them.

Thanks much for your help!!!

In my introduction thread, MetroMPG said he didn’t believe the trailer would affect mileage much if it was behind the car. Any other opinions or ideas?

Does it really have to be enclosed?

How many miles per year do you plan to pull the trailer, and at what speed?

The lower your walls, the better the aero efficiency, and you'll want to cover the top. When my 2ft walls are up, but nothing is in the trailer, it's like a parachute is attached to the car. When it's full, it hardly affects mileage at all.

What are the mixed reviews about the Harbor Freight trailer? Mine has been great, and folding it make storing a breeze. My complaints are that it uses a 1 7/8 ball, which is much less common than 2", the wiring for the lights are garbage and should just be thrown away instead of installed, and it takes forever to assemble (there's about 90 bolts) plus building the deck and sides.

Here's my trailer album:

https://ecomodder.com/forum/member-r...s-trailer.html

The bed on my little trailer is a whole 4-foot square. The tongue is 4-something feet long to boot, presumably to minimize tongue weight. Add another 6" on either side for the wheels/tires/arches.

I can't even see it in the mirrors of out SUV when towing it...makes me paranoid.

A small trailer totally in the aeroshadow of your vehical, should not add air resistance, unless it begins far enough back that the airstream has begun to converge to the point that it slams into the front of your trailer. The best design would be one that catches the airstream just as it begins to drop, and guides it to a taper at the rear of your trailer

There are many ideas in this forum, as well as a template in "Garage and Tools" If you don't want to do the curves, a straight taper would be an improvement over a rectangular prism of a box.

Carry-On Corporation (www.carry-ontrailer.com) makes a 4X6 cargo trailer that might meet your needs. I've had their 5X8 trailer for several years now. It's a well built low cost trailer.

Good morning everyone! I’ll do my best to answer everything!

Enclosed- Yes, this will be a small “luggage trailer” to haul camping gear, or all the crap my parents buy my kids at Christmas. I have a small flatbed, 5x10 to haul lumber and sheet goods on, but that trailer is over kill, and the weight and width of it destroys mileage.

Mileage- At least 2 750 mile trips to Canada and back, as well as several trips to Cincinnati, which is about 300 miles.

Speed- I drive the minimum that feels safe. Around here, the speed limit is 75, so most people are doing 80-85. I usually run around 70 unless the traffic is heavy, then I pick it up a bit so I’m not a menace.

HF trailer- to be fair, I've heard as many positive comments as I have concerns. The primary concerns seem to come from tires, wheel bearings, and some have said that bolting it together doesn’t make it rigid enough.

As far as the design, it’s still up in the air a bit. I’m very handy, I built houses when I was a little younger, and my dad was a mechanic, so I grew up wrenching. I want to build something for the satisfaction of doing myself, and to save a bit of money. Trailers that I’ve seen that look like they’d be suitable seem to cost about $3000.

As for the aero, It won’t be as tall or wide as the Forester, so the front should be mostly protected. think from my reading that I would line the template up on the highest point of my tow vehicle, then fit the trailer inside the template, ideally matching the template profile and the lines of the trailer? I planned to bring the side panels straight across the wheel opening as a skirt, and I could do a sheet aluminum belly. Also, I think I’d do a Kamm back to keep it to a reasonable length. I’m still researching the ideal Kamm back length wise.

Thanks for all your questions and comments!

Would this be big enough?

https://images.homedepot-static.com/...96-64_1000.jpg

If you are thinking of spending that much, here is an aluminium boat trailer that can be the start of your project. You can shorten and modify it to your needs, and it has a highway speed axel https://www.jamestowndistributors.co...t.do?pid=52765

That would be ideal. Be sure to account for the airflow drop off the rear of your tow vehicle.