For those that tow beyond capacity, or without necessary driving skills
 

Happened July 24, 2017. I assume from the pics they were well beyond capacities. Luckily no one was injured.

quite possibly just an equipment failure too. A WDH with sway control where either the sway or perhaps one bar failed? Not properly equipped is the most likely. I would bet they had a WDH without sway control.
That TT is well within the capability of an expedition to tow if properly configured.

I don't think that expedition is rated to tow a TT that large. The new expeditions coming out shortly will be rated to 7700lbs.....older ones definitely not rated that high.

I'm guessing no WDH/anti-sway device.

I know folks that have them that size. Some of them really aren't that heavy. I had the argument with a friend with his Expy too. Then he showed me the numbers. I was pretty shocked. Not defending this guy just giving them the benefit of doubt.

A couple of things in my opinion.

A lighter trailer will start to sway easier than a heavier one. That's a trade off you have to accept when trying to pull longer travel trailers.

Secondly, notice how the "filming" vehicle also moves to the left in almost the same spot? I'm thinking a strong breeze initiated the sway and it became a "pilot" induced oscillation that got worse and worse.

Thirdly, I think the driver of that SUV did the opposite of what you should do (if at all possible) and that was give 'er gas to pull out of that oscillation. Slowing down (if you watch that grey car to the left of the "suspect" unit for comparison of speed) is the worst thing to do!! You are now applying pushing physics to the pivot point resulting in pushing the rear of the towing vehicle. By applying power...you will pull the trailer back into submission, so to speak.

And, as stated already.....lack of proper equipment could also have contributed.

Obviously we don't know the weights and his hitch set up but without a doubt I would say first thing is too long a trailer for that SUV.

the numbers? You think that expedition has a higher payload than an F150?

There's a reason those things aren't rated to tow nearly as much!

Regardless of the weight, that is Too much trailer for an SUV. Inexperienced driver to top it off. Just because you think it can, doesn't mean you should.

Our 2008 Expedition is rated at 9,050 lbs. Now I would never tow that much with it but they have very good tow ratings. It also has a higher payload capacity than our F-150.

"Pilot induced oscillation" ? You're not one of those airplane people, are you?? :)