Forum Discussion
dlleno
Jul 17, 2018Explorer
dlleno wrote:
Can someone tell me the distance between the center of your trailer axles and the king pin? I'm looking for the diagonal between wheel center and pin tip.
I'm also looking for an estimated vertical motion of the pin during normal use. Is this 6 inches? This would include tv suspension flex of course and (in the case of a ts) hitch deflection. I'd like to do some calculations to estimate the forward chucking motion of a, trailer under normal tow
OK I made some assumptions and found that mathematically I can account for around 1/2 inch of forward motion just due to downward articulation of a fifth wheel (at the pin) where the trailer axle is 24 feet from the hitch. So the trailer noses into a bump, squats the truck and any other vertical suspension components, and the trailer will also push the TV forward a half inch and then jerk it back at least that much or more. If the rebound is just as severe, you can count on a full inch of total peak to peak movement.
No wonder chucking is an issue with solid hitches. That was enlightening. Thank you durb for your analysis and diagrams sent via email!
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