If you've ever wondered what happens when you lose control of your U-Haul trailer at highway speeds, here you go.
The truck got caught out when its attached trailer started fishtailing.
Indeed, if you're new to towing trailers and your trailer starts fishtailing, U-Haul recommends that you take your foot off the gas and slow down slowly. Don't use the brake, just let your speed drop and you should be fine.
What It's Like To Lose Control Of Your Trailer On The Highway