perhaps the young bucks of today dont go round checking to see if the clip for the handle of the fifth wheel is in position. Even though some fifth wheels are not the same, eratic driving or fast driving round islands and cambers can dislodge the trailer from the fifth wheel depending on weight of load.
NB pin on a trailer is only two inch, you could be carrying at least 25 ton.
REST MY CASE!! 
I think you are being unfair here to the Truck manufacturers. A Truck chassis is normally delivered without a fifth wheel and is fitted either by the dealer or the workshops. The choice of make is either down to cost or previous experience.
If you have a new type of coupling or mechanism, make sure you know how it works. Make sure you put grease in the jaws and on the clamp. as well as the lever and locking mechanism. The clips are there to give a visual check, if the clip wont fit its not coupled up properly.
Of course I dont check properly, like crawling under the trailer to make sure the jaws are engaged, I just do a tug test and you can also tell by the sound when you are used to it
And i have never seen a 2’’ pin shear through driving too fast round corners.
Even in an accident the pin will hold it is normally that the fifth wheel plate is torn of the chassis.
I think we’re questioning the Fifth Wheel Manufacturers here, and not the Truck Manufacturers.
The choice of make is either down to cost or previous experience
.
However I would like to think that the Truck Manufacturers will listen to the verdict of firms like Jost etc. and their reluctance to admit there may be a problem not caused by the drivers inefficiency and vote with their feet when such firms are invited to tender for new model business.
It’s the easiest thing in the world to cover up a problem with the platitude of driver error , but it takes a totally different type of manufacturer to listen, and look at the evidence of how often this is happening to one particular design and do something about the design.
Even though some fifth wheels are not the same, eratic driving or fast driving round islands and cambers can dislodge the trailer from the fifth wheel depending on weight of load.
NB pin on a trailer is only two inch, you could be carrying at least 25 tonton.
REST MY CASE!!
Sorry but I disagree…the design of fifth wheels should,
and is, sufficient to cover any of these eventualities. If you uprate or downrate the weight a unit is plated for, it only alters the way the whole thing is bolted on, the design is constant and when you think of what could happen if a trailer comes adrift in a busy town centre, by a bus stop etc, then I maintain that the evidence suggests there is a problem and it should be addressed.
Pat
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