If it wasn't for the Thule's ability to tip its bed to either side as well as in a normal rearwards fashion, this would merely be a darn nice trailer. With the capability to empty the 121x68-inch bed to the sides, it becomes an incredibly useful and darn nice trailer. If you have a use for a dump trailer, that is, which would likely include most of us, although, some more frequently than others. If nothing else, a stock flatfender or early CJ-5 will fit just fine, especially with the optional loading ramps.
When first laying eyes on this trailer at the 2006 SEMA show, we almost walked right by it. After all, it's a relatively homely apparatus clad in hot-dipped galvanized, press-formed panels over an equally visually uninspiring and rustproofed chassis.
Then, at last glance, we caught a glimpse of its true beauty, made a rapid entry into to the Thule booth, and didn't leave until all their representatives were tired of our questions. By then, the expensive rented carpet was dampened by our enthusiasm-induced drooling after crawling around and looking at the undercarriage, and what made this trailer tick.
True, we've already confessed to having a trailer fetish, but this one is special. Its most striking feature is obviously the ability to raise either the front (in regular dump-bed fashion) or have the load dump out to the left or right side, all at the push of a button. Oh, and by positioning two pins and opening a pair of latches-this obviously beats shoveling the load out by hand.
A Simple Concept That Works
One could make a trailer bed tip in different directions all kinds of ways, but Thule's approach is about as simple and effective as it gets. There's a trailer ball in each corner of the chassis and matching "couplers" on the bed, which the bed sits on. By putting pins at the desired positions (on either side, or at the rear) it locks that part of the bed down, yet lets it pivot freely in two directions.
To raise the bed, an electric motor drives a hydraulic pump which acts on a ram, and the mechanism for limiting the hydraulic ram's travel is equally simple and effective. Normally, the ram would be sized to run out of travel at the max lifting height, which works fine when lifting only the front of the bed, but the geometry changes when tilting it to the sides, leaving too much of the ram's available travel left when the bed's at its full 38 degrees of side tilt. This was solved with a tether between the bed and a chassis-mounted valve that shuts off the pump's flow. The whole setup is basic and practically foolproof.
Most everything on this Thule Three-Way Tipper is industrial quality, including the latches. While the ones for the bed sides are slightly less sophisticated, the tailgate is held by real truck stuff. Notice that the tailgate can be opened either at the top or bottom, the latter for spreading. Also, it is easily removed altogether, just like the front and side panels. | 
Underneath the hot-dipped galvanized bed are all the mechanisms that work the bed. From left to right, a marine battery, then the remote for raising and lowering the bed (it has magnets on the back to hold it in place, which can be very practical), followed by the reservoir, hydraulic pump, and motor. At the far right, the ram is mounted on a base that pivots in two planes, while the top mount is of a ball and socket type. Also visible is the front torsion axle and part of the parking-brake setup. | 
Like the 3,850-pound-rated axles, the coupler assembly is made by Knott, a big German outfit, and consists of a surge brake that releases after half a turn of the tires when backing up, a four-wheel parking brake, a lift handle, and a swiveling (to some extent) coupler which also shows if it's connected correctly. Notice that the jack has a "somewhat-quick-release" in addition to the regular crank. The black toolbox to the right contains the remote and its 9-foot cord, with room for much more. |
Built for Long-Term Use
It appears that Thule sought out some of the best European components available when gathering the hardware for the Three-Way Tipper. Most everything, such as the coupler, latches, axles, and the remote, are all industrial-strength items. Slim LED combination reflector/side marker lights, however, contrast with the fragile-looking incandescent taillights (that are easy enough to change out for something common if one breaks).
Built primarily for contractors, the Thule Three-Way Tipper can haul all sorts of cargo, including machinery, weighing up to 5,700 pounds. There are four D-rings to tie to per side, and optional ramps that slide into pockets under the bed when not in use.
Is America ready for something so functional, yet completely devoid of flash? We sure hope so, or you'll miss out on one incredibly useful trailer.
But ... Why?
An ingeniously simple setup, trailer balls at each corner of the bed fit into sockets on the frame. There are two pins, similar to those for a trailer hitch, which keep the ball in its socket. By putting the pins at the rear, or at either side, they create the pivot points for the bed. Thule even went so far as to make the pins and sockets somewhat uninterchangeable so that one can't install them at diagonally opposite corners of the bed. While that would've been our preferred transportation mode, it is more foolproof this way.
Maybe it's because everything else is so very right on this Thule trailer that the things we didn't understand stood out that much more. Here are the nitpickings, and explanations with potential solutions.
* A 2-inch coupler. We're sure glad we asked before driving 600 miles to pick up the 7,770-pound-GVWR trailer since we took for granted it'd take a common 2 5/16-inch ball. Yes, there are 2-inch balls rated at up to 10,000 pounds, but they're not the norm. Order a different size coupler from Knott-pintle setups are available too.
* A "Flat-4" trailer wiring connector. Again, we were taken by surprise and arrived with a common seven-pin connector. To run the lights and charge the battery requires five wires. Thule's explanation does make sense; completely separating the tow vehicle and trailer batteries is a more foolproof setup, though it mandates charging the trailer battery separately. Rewire to your liking, and then pay attention. Or, leave things alone and buy a good battery charger-we're sticking a solar charger on the toolbox.
* Radial tires. We had expected trailer tires, ideally bias-ply, but if the trailer is used daily and mostly on pavement, the supplied commercial 195/70R15 Continentals may be a better choice. Able to support 1,984 pounds at 65 psi each, they are well suited for the 7,770-pound GVWR.
* Torsion axles. Unable to follow the terrain like a set of less expensive leaf-sprung axles, they're best suited for pavement use, yet the ground clearance is better. Considering the popular inner-city use these trailers see in Europe, it makes sense that they come with torsion axles.
* Bungee battery hold-down. While simple and adequate, we'd like to see the battery held down by something more substantial than the bungee on the battery cover. Making a more secure battery hold-down is very easy.
So, not even our favorite trailer to date is flawless in our opinion. Big deal. We can easily live with these things-except, maybe the battery tie-down. Then, when one of those odd taillights goes bad, we'll stick standard 4-inch round LEDs back there. They can be had for just $10 apiece these days, and the marker lights are LED already.