Dropped Trailer??

It's possible it wasn't quite locked either. Lack of lubrication could have prevented it from completely locking. Kingpin not quite slid in all the way. A lot of you guys don't seem to take the time for lubrication. Just hook and go with dry plates.

I get 5th wheel slop shortly after the truck gets serviced. That jelly that pretty much every shop uses don't last long and in the winter time. Actually freezes up. I buy my own bottles of that lucas 5th wheel lube. That stuff is the BOMB. I have to leave it in the cab in the winter time though. To keep it warm and flowing.

 

Just a thought... are you SURE someone didn’t pull the release handle on you when you weren’t looking? Like maybe you hooked up the trailer and went inside to get paperwork or something, and unknowingly parked in someone’s way and they did it to get back at you? Lol it may sound crazy but people do that. I’m just trying to think of another possibility here.

I’m glad you were able to save it without any damage. I dropped a trailer once with a yard horse, it is definitely a scary situation.

 

Anyone doing this long enough has probably dropped one, including me on a 90 degree day 30 years ago with a heavy load of paper. To hopefully prevent this from happening again always check these items below.
1. With a flashlight look under the trailer at the back of the 5th wheel to see that the jaws are out/closed/locked.
2. Look at the side of your 5th wheel to see that the “bolt” is slid in fully. If you look at the side and rear of your 5th wheel when it is released you will see the difference on both of these.
3. With the hand valve/hill brake pulled and tractor and trailer yellow&red valves pushed in gently tug against the trailer after you have moved from the original spot you hooked.
4. Make certain you have no gap between the top of the 5th wheel and trailer plate. Highpinning the trailer slightly.

I have had a converter dolly 5th wheel come loose after doing all of the above steps, luckily in the parking lot of the terminal. Stuff does happen and 5th wheels do fail on occasion, but not often.

 

102% chance someone pulled your release handle. They don't shoot out on their own. They are held in by a tension spring. Some, like mine, you have to lift up and forward then pull out and lock it out-- so it's like a 3 points molly just to get the jaws open.

 

I worked for a company early last year that ran new Cascadia ultra-light trucks with a slightly shorter sleeper and a fixed aluminum skid plate. My first week I hooked up a trailer in the yard, it clicked in nice and I climbed under and made sure the jaws were locked in. Left the yard and turned the first corner and the trailer dropped. I couldn't understand how or why. When I looked at the locking jaws they weren't fully engaged and the pin pulled up and out as I turned. So even a visual inspection will sometimes miss a problem. I found out later than several others in this fleet had also dropped trailers under the same circumstances.