This occurred in Southern California. New trailer and new Ford F-250 Diesel.
There is a 1 hr vid on the recovery of the truck and trailer on line at YouTube.

https://www.bing.com/search?q=Fifth+...APIPH1&PC=APPL

Don’t known what happened, tried to find it. The hitch was attached via bed rails. The entire rear bed rail pulled out of the bed. Hitch was hanging on the pin box. This truck may have a aluminum frame. It would be interesting to see the frame.

Dave

 

I also saw this video and have an opinion. The truck appeared to have after market wheels, which were probably the cast aluminum type. I don't know about Ford trucks, but my '06 Dodge came with forged aluminum wheels. The truck may have had a left wheel blowout or wheel failure. This caused the truck to swerve violently the right and came to rest under the front of the 5th wheel. When the truck was righted by the wrecker crew, the center of the left rear wheel was entirely broken out. I don't feel that a forged wheel would have broken. Just my two cents.
John

 

I saw the wheel as well. Don’t known what caused the accident.

My 2 cents as to what caused this is, the truck and trailer were new according to the guys working the accident. I thing the trailer brakes did not work which caused the trailer to over run the truck when hard braking was demanded for whatever reason by the driver. The trailer force ripped the bed rail from the frame causing the truck to be rolled and pushed off the road. The tire was incidental to the problem.

Still trying to find out.

Dave

 

It was reported the wheel failed causing the accident.