Swaying trailer

[us71na]

So, the other day I was going along on the interstate and was passed by a SUV towing about a 21 foot single axle travel trailer. As I followed along, I noticed the trailer was swaying (weaving) back and forth a bit. We were travleing about 63 mph. When traffic bogged down a bit (60 mph) and the trailer slowed, the swaying stopped, then resumed as it got back up to speed. When they pulled out to pass another vehicle and speeded up (~65 mph) the swaying stopped until they came back to the driving lane and resumed their original speed.

Is this cause for concern? If so what causes a trailer to do that?

[JFlightRisk]

That sounds like a couple of problems to me. There was no sway bar(s), and maybe the tongue weight was too light, like it was loaded too heavy towards the rear of their TT. Unequal TT tire pressures would exaggerate sway also. I've observed the same scenario myself, by a passing mini van with a single axle TT, going just a tad too fast. They HAD to have been able to see and feel that sway.

[Jagiven]

Sway is always an issue. This summer I saw something like you were describing. We were on our way home from BSA summer camp. Got passed by two scout vehicles hauling enclosed trailers (trailers had the same troop info on the sides). If I recall correctly one was a single axle and one was a dual axle. Both tow vehicles in my opinion were to small for either trailer. I think it was the single axle trailer as he passed me (going way to fast). He was all over the place the place. I actually slowed down, as I did not want near him. I suspect he was improperly loaded, trying to keep the tongue weight down as the vehicle was to small. I used this as a teaching moment for my 16 year old.

I have found some lanes on the interstate, have rut like groves in them from lots of heavy semi traffic, and the trailer an play a little funny game, trying to find a spot in the rut. When that happens, I try another lane. I have a lot of trailering experience to notice what is happening, and not like the feeling.

Speeding up can eliminate sway at least for a short time. If you get into a sway condition, what the experts say to do, is hit the manual trailer brake button, and accelerate the TV. This will straighten out the combo. Luckily, I have never had to try this.