Two Axles Vs. One??

[jimmoore13]

I'm trying to rationalize an experience.

My previous rig was a big, highwall popup with a single torsion axle. Quite nice.

My new rig is the Jay Feather X213 with two leaf spring axles.

Our favorite spot is 11+ miles into a rough, washboarded and potholed dirt road. The road is hard on everything, but particularly hard on trailers. The local flatbed towing company does a land-office business rescuing rigs with broken springs...literally collecting them, dropping them at their sites for the weekend, then picking them up on Sunday (or whenever) to haul them out for spring replacement.

Getting to the point, my single torsion axle was bulletproof, but the trailer rattled itself apart, and my first act on arrival was to look for screws and other parts on the floor. I had to replace several cabinet hinges on the larger cabinet doors. The washboard shook things apart DESPITE the fact that I aired down the tires when I hit the dirt.

Last weekend was my maiden voyage in the new Jayco. What a difference. I kept the tires at the factory recommended 65 PSI. Despite the fact that the Jayco has leaf spring suspension instead of torsion axles, the tow was noticeably smoother! Nothing rattled loose, things stayed in the cabinets, and I could feel a real difference from the driver's seat of the TV.

The old rig would yank and pull on the TV as it shuddered over nasty washboard and dropped into potholes. The new one seemed to float much better over the rough stuff...potholes in particular.

So the question. Is this for real? Are tandem axles the magic sauce for ironing out the rough stuff? My hunch (half-baked hypothesis) is that while one tire is, for example, dropping into a pothole, the other is holding the rig up and preventing all the lunging up and down. On washboard, the two tandem wheels "average out" the ripples and keep the rig more stable. But that's just a hunch.

If anyone has solid evidence that this isn't just my imagination, I'd love to see it.

Thanks in advance.

[DocBrown]

We had a single axle hybrid trailer with a torsion axle. Never had a single issue with it. We towed it all over the country, many thousands of miles. Towed beautifully. Our current hybrid has 2 axles. Also torsion. Tows about the same, just heavier!

[mokurt]

The key is drive slow on roads like that.

[Screwby]

I think there’s quite a big difference in dual vs. single axle in the trailer bounce. It helps having dual axles because ideally there’s one tire making contact with the surface of the road at all times. You can watch videos of a single axle taking bumps as opposed to a dual axle taking bumps, huge difference. Single axle trailers have the tendency to bounce trailers at speed where dual axles distribute the load.
I think the weight of the trailer comes into play as well. Single axle trailers are usually lighter so they bounce more. Dual axle trailers are usually heavier so they don’t. Watch a single axle little U-Haul trailer go down the highway, bounces around like a pogo stick.
That being said, I go as slow as humanly possible on those kinds of roads. Just because it’s not bouncing doesn’t mean it’s not flexing like crazy.

[muckinfuss]

Clearly the most obvious advantage of two v one.....if you have a blowout a dual axle set up will be more stable and less inclined to flip....especially at highway speed.

[jimmoore13]

Thanks all.