Flicking through the gogglebox this evening, they were showing winter rescues or whatever on C5. They were recovering a Magnum and a tipper that had gone off the road on a bend. as they were dragging it backwards towards the road, the difference in angle between the trailer and cab being upright seems like 30/35 degrees?
Which leads me to the question, how much flex is there in a fifth wheel coupling? (by that I mean how much can the trailer roll from side to side?)
Hardly any, the difference in the angle of the cab to the trailer will be flex in the tractor unit chassis and the cab suspension, of course the trailer could be mangled if it’s been in a crash 
Any sideways flex is purely through chassis twist.
Truckbling:
Any sideways flex is purely through chassis twist.
Not quite true, there can be quite a lot of side ways movement between the trailer and the fifth wheel with out flexing the chassis, more so with an empty trailer!
weeto:
Truckbling:
Any sideways flex is purely through chassis twist.Not quite true, there can be quite a lot of side ways movement between the trailer and the fifth wheel with out flexing the chassis, more so with an empty trailer!
That’s just splitting hairs. The 5th wheel is not design with lateral movement in mind. The pivot points are purely for hills. Granted there is a little “give”.
Truckbling:
weeto:
Truckbling:
Any sideways flex is purely through chassis twist.Not quite true, there can be quite a lot of side ways movement between the trailer and the fifth wheel with out flexing the chassis, more so with an empty trailer!
That’s just splitting hairs. The 5th wheel is not design with lateral movement in mind. The pivot points are purely for hills. Granted there is a little “give”.
There is quite a lot of side was give between the fifth wheel and trailer plate.
I worked internally in an opencast coal mine driving time expired artic tippers, because the site was rough to say the least falling over when tipping was common one in particular screwed the chassis practilly to right angles as the unit stayed level and the tipper box on its side pin still engaged I thought well that one has seen its last load. But the shovel emptied the coal out and lifted it backup it was taken to the workshop and a new tipper ram put on and was back on the job the next morning and was as square as a die. So it just shows how much a trailer chassis can flex and return to square one. Eddie.
^^^^^ hooks law.
Dunno myself, but when one of our trailers (low loader) tipped it tore the fifth wheel from the unit, unit stayed up right…just.
Drift:
Dunno myself, but when one of our trailers (low loader) tipped it tore the fifth wheel from the unit, unit stayed up right…just.
might have a double oscillating fifth wheel which can move left to right ( but you are supposed to have them locked for road use. and they cost a fortune ) i have one that i want to put on my kenworth because it has a aluminum chassis and the double oscillation would take the strain of the chassis.