The dolly has made it much easier for me to move over a half ton of boat and trailer.

Rolling a trailer with ease

If I had my druthers, I wouldn’t have to man-haul my boat trailers to get them to the car to hitch them up. The caster on a trailer jack works okay on pavement, and only marginally in my backyard in the summer when the lawn is dry and hard, but on gravel and damp sod it’s a struggle to get it to roll or pivot.

I recently sprang for the Seinoy trailer dolly and wish I’d bought one sooner. It took about 20 minutes to assemble; metric sockets would have been much quicker than the crescent wrenches I had to resort to. The dolly weighs 31.7 lbs and feels quite solid. It comes with a 1-7/8″ ball, which fits the couplers on my two small trailers. The 12″ x 4″ pneumatic tires are like those used on wheelbarrows and roll easily on pavement, grass, and gravel. The dolly has a stable 24″ wheelbase and the wheels spin on bearings slipped over a 0.9″ steel tubing axle. A sturdy 1/4″-thick steel bracket supports the hitch ball and is connected by a brace to the 4′ long handle.

To roll a trailer-jack wheel across this soft lumpy ground, I had to lay down a path of boards. The dolly isn’t bogged down by it.

The first time I used the dolly—on the trailer I don’t have outfitted with a jack—I was impressed with how easily it can lift the trailer’s tongue from the ground. Raising the handle lowers the hitch ball, and after the ball is steered under the socket of the trailer’s coupler, lowering the handle lifts the tongue. The long handle not only provides a lot of mechanical advantage—4.4 to 1—but also entirely eliminates the back strain of lifting the tongue up by hand. I just have to put my weight on the handle to push it down. The tongue weight on the trailer I’ve been using the dolly on is 137 lbs and the weight of the trailer and the Caledonia yawl it carries is between about 1200 lbs. Seinoy sets the dolly’s capacity at 600 lbs, so even though I’m doubling the working weight, the dolly hasn’t shown any sign that it’s suffering under the load.

The handle comes to a convenient height for pulling; it just lines up with my arms and there’s no fighting its angle. Pushing is almost as easy, I can set the handle in the crease of my hips if I need extra power. Steering with the dolly is a breeze—it easily spins around the hitch. Lowering the handle moves the hitch ball a bit past directly over the axle and presses the handle down on the stand that’s bolted to its backside.