Towing Tear Drop Trailer

I like it! But they run from $5000 to $12000. Mine cost less than $1000.

I don't think there would be any warranty issues with the smaller units. Basically you've got to break it to get into a warranty situation. And these things aren't going to break a Prius within the warranty period. If you insist on carrying 5 people, a full trunk, and 500 pounds of gear inside the teardrop then maybe you could break something. But offhand, I don't think that 5 people are going to fit in one of these...

 

One of my ideas was to drill a pattern of holes in the plywood. Say 1" circles on 2.5" centers over the entire sheet (except for the edges). Then fill the holes with foam. Could probably save 100 pounds, with very little loss of strength. But I'd have to experiment to find out just how much material could be removed and still have sufficient strength.

Another idea is DIY honeycomb plywood. Start with 1/2" plywood, drill 1/8" holes on 3/8" centers, skin both sides with 1/8" veneer. A lot of work, but could be light and really good looking.

For aerodynamics, my idea is to make it a pop-up. A cap that drops down around a half height perimeter. Lots of problems to solve for that one though, such as the lifting mechanism, sealing, door design...

 

Nice Rob. I been planning to build one for some time, haven't started. Got anymore detailed pics/plans? Also, wouldn't it be more aerodynamic and simple to use the wedge design? Just a thought. I might go that route. And 32mpg for a camping mobile is by far the best mini motorhome.

 

If the camper will only sleep two, why not just sleep in the car?

 

Fantastic Rob. As an Engineer, I applaud your project and ideas. Cost and weight right on.

 

What part of "the Prius is not designed for towing" do you not understand?
Your collective arrogance amazes me.

 

Toyota doesn't "recommend" towing anything with a Prius. Sure it's not going to burst into spontaneous or immediate flame if you do.

I love camping. I like those tear drop trailers BUT I certainly wouldn't put my vehicle at risk just because I thought it was light enough not to do significant damage.

In my opinion you have to use the right tool for the job, and there are a lot of jobs inwhich The Prius IS the right tool. BUT towing something, even if you can get away with it, why take the risk? I'd lean towards tents, OR simply renting something for that camping trip.

 

Thanks! I looked at quite a number of teardrop pictures and plans. One that I really liked is called the "Desert Dawg" - just Google for it & it should show up. My trailer is a minimalist version of the Desert Dawg idea. The Dawg and my trailer use only flat panels, while most teardrops use curved surfaces. The curved surfaces certainly look nice, but they also look like a lot more work. There is another design called "Grasshopper" that is more of a wedge shape.

Many of the formal plans give exact dimensions for every part. The problem with that is that lumber doesn't come in exact sizes. A 4x8 sheet of plywood from Lowes may be 1/2" longer and/or wider than one from Home Depot. Same deal if you buy what's supposed to be the same item from a different shipment. Exact sizes work for kiln dried pieces that are cut on a CNC machine, but rough pieces from the lumber yard are exactly that, rough. In houses, the problem is solved by using multiple layers - the large pieces don't join very exactly, but smaller trim is used to cover up the gaps.

Registration of a trailer with the DMV is really easy if you buy a kit or fully completed trailer from a place like Harbor Freight. The trailer comes with documentation and a serial number ready for registration. Registering the bare frame is cheaper than registering a completed teardrop, so go see the DMV as soon as you've got the wheels on... If you custom build a trailer frame, then the DMV will want receipts for the materials, maybe even some formal drawings. I get the impression that you're better off buying a kit even if the only part you end up using is the one with the manufacturer identification and serial number.

 

Since Toyota doesn't give their reasoning, I had to consider what it might be. Rules are mostly a list of problems that have been experienced, or at least worried about. Toyota clearly doesn't want to recommend towing with a vehicle that runs out of power on a long uphill pull. I can understand that, but that doesn't mean that I can't come up with a different decision. The problem that shuts down their permission is something that just doesn't come up in my usage.

Some people look for rules to follow. Others look for rules to break. I tend to evaluate the consequences of breaking rules I find objectionable. In this case, I don't see any consequences. In fact, it's right up there with doing 66 mph in a 65 mph zone.

You can get a ticket for doing 85 mph in a 65 mph zone. In northern California it will be for speeding. In southern California it will be for obstructing traffic. The laws are the same, but the enforcement has different priorities.

 

... and what makes you an expert on the reasoning behind the Toyota warnings?
Seem to me that one might want to consult the people at Toyota before running off and doing something that is clearly beyond the pale.

 

For those of you who are interested, there are other trailer discussions here and more listed here.

It would be hard to beat $1000 in material costs, but plywood may not be the best material. It doesn't curve well, and it tends to be rather heavy. With some experimentation and a higher budget, I would think a simple stick frame covered in skin ply, and then fibreglassed, would be light, strong, and waterproof. If you wanted to get fancy, you could build the shape from foam, and then cover it with fibreglass and epoxy resin.

 

+1 bring sleeping pad or inflatable mattress.

 

Well, for one thing it's my car. And for another, this "rule" that you reference doesn't seem to have any legal stature in my jurisdiction (California). When I registered the trailer with the DMV, they wanted documentation about the trailer and about me. If there were some rule about the vehicle used to tow it, wouldn't you expect them verify that the car towing the trailer was approved to tow it?

Towing packages are available for some cars. They generally include extra transmission cooling, maybe a larger radiator, a trailer hitch, wiring for the trailer lights, maybe a heavy duty suspension with stronger springs on the rear, and so on. As far as I know, the state vehicle code in California makes no distinction as to whether such towing packages are installed or not. It may be recommended that a towing package be installed, but it only rises to the level of recommendation, not law.

I violate several other Toyota recommendations. Like 7500 mile oil changes with synthetic oil. Tire rotation happens whenever I think it's been too long, like 10,000 or maybe 15,000 miles. I'm going to change the transmission oil soon, long before the Toyota recommendation. I installed TPMS on my spare tire because I like the idea of knowing when the spare is too low. These are all judgment calls where I differ from official Toyota policy. They all seem perfectly reasonable to me, as does my towing a small trailer. The zero tow rating smells like corporate CYA, with a bit of marketing (buy bigger!) thrown in.

 

RobH,

You done good. Enjoy your trailer.

You have a great combination of simple, functional and light.:rockon:

 

I would not mind towing something in the future. I think you would be safe towing with a Prius as long as you kept the GCWR below the Prius's GVWR and had a low tongue weight. That Rascal teardrop should tow just fine with a Prius.


Posted from my iPhone via the Tapatalk app.

 

I personally do not think that towing a 1,000 pound trailer with a G3 is "beyond the pale", but I do acknowledge the fact that Priuses have a "0 pound" tow rating, and I'm not sure how the CVT would react to long term towing.
IIRC, a G3 is only rated to haul 800-some odd pounds of people and cargo, and given the obesity rates in America, I'm sure that there are a lot of G3s out there that are called upon to haul more than 100-percent of their cargo capacity.
Should be no problem, really. It's just a SWAG number anyway.
However (comma!) I wouldn't want to (try to) get transmission work done on a G3 under warranty with a 2" receiver hitch bolted to the stern!

I briefly considered getting a G3 for my personal use, but since I have an 1,100 pound lawnmower and 2 motorcycles well......no new Prius for me!
I'll have to settle for another econobox for my personal use when gas gets too expensive for me to continue to drive my 09 Truck---something with at least a 1,500 pound tow rating.


Short answer: Yeah, you can get away with it...maybe...even probably, and it's your car, but it will void the warranty if the CVT dies prematurely.

I like the home-built trailer!
Cheap. Simple. Effective.

Good Luck!

 

Well said Rob. I plan on building a project similar to your. I am glad to hear others have had success towing with the Prius.

 

FYI - Google "quality S" tow hitch for a low cost class III (5,000 lbs) hitch.

I have one - it mounted easily, and is clearly better suited for moving your 3,000 lb loads...:fish2:

 

I'll definitely be unhappy if the transmission dies. It's already out of warranty!

I monitor water temperature with a ScanGauge. No problems in that department. Now if I could monitor MG1/MG2 temperatures that would be better. The data is available, but not with the current ScanGauge. Maybe there will be an update that makes MG1/MG2 monitoring functional.

Since the transmission doesn't have a fluid coupling like ordinary automatics, there isn't any heating effect from that source. But MG1/MG2 are electric motors that certainly produce their own heat. In general anything that is monitored by the computers should raise a DTC and the red triangle before there is actual damage. But I don't know for certain that there is a MG1/MG2 overheat DTC that occurs before there is actual damage. I'm certainly going to change the transmission oil more frequently that Toyota recommends.

 

Did that improve your gas mileage by any chance?