Saw a Yellow trailer in the middle of the highway

Every terminal I was at had them. Back in the day CFCC and CF had I scale on the dock to check weights.

 

I pulled double oil tankers with single screw for a few months before I got a semi trailer. That was real rough. The oil was only loaded about 3/4 of the way to get to 80k. We had a driver lose the rear trailer on I5 and spill all over the highway.

 

I think its very unlikely the dolly went with the rear box. The way that hook is attached to a pup you would have to rip the rear end off the trailer to get it off. And there are 4 safeties that hold the dolly to that hook. One is the top of the hook itself which locks in place and is supposed to be pinned as well. Then there is an air driven pressure plate pressing against the ring on the dolly, and if it isnt working then the wheels on the front box arent rolling either. And last but not least there are 2 chains that hold it as well.

Most likely he high hooked the rear box and didnt notice it, or the pin released. I have had the 5th wheel pin on the dolly actually release on me. In fact Ive had it happen on 3 different occasions (yes, I know the trailer was locked because I always shine a light up to make sure its locked). All 3 times the temp was -25 degrees or colder. But luckily it happened in the yard at low speed and always after a 90 degree turn to the right.

I have also had several occasions where I had to hook the boxes in reverse order (heavy on the rear). In 1 case, the rear was 20,000 pounds and the lead was 2,000. I had a tandem axle tractor and the heavy boxes in these cases were 26 footers, so I had to put the 28 footer in the lead or when I turn I would rip the landing gear off the trailer with the frame of the tractor. It gets squirrely as hell that way when you are breaking, but no way would it cause the rear box to release. But it handles fine just going down the road.