TD Beej wrote:I am trying to understand the dynamics of trailer handling so I can make the best choices.
The point is to make informed choices and to do that one needs to be informed.
Now a multilink suspension is attractive for a number of reasons but it also has drawbacks and when the choice is made it will be done knowing why and not because anyone may think it is "overkill".
I'm sorry if it seems like we are not taking your ideas and concerns seriously. Trust me, we are.
But, this has come up before, and guys like me and MJ and others have been towing trailers of all sizes for many, many years.
I also have been through track driving schools, and have a lot of performance driving seat time.
It sounds like your initial issue with "sway" is perhaps more of an issue with trailer "control." The two are not really the same.
The sway problem we have been addressing is a rhythmic back and forth motion that happens without any input from the TV. The TV is going perfectly strait, and the trailer starts to sway in a rhythmic fashion.
Now, the control issues associated with a trailer reacting to a change in directions from the TV is something else. In that kind of situation, the weight of the trailer, it's center of gravity, the weight of the tow vehicle, tongue length, and other factors effect what happens.
In theory, a top-notch suspension SHOULD help keep, or return control. But, again, the value of such a suspension will vary depending on all those other factors.
I have 600-700 pound TD with a low center of gravity. My experience tells me that my TD is not going to benefit much at all from a more sophisticated suspension.
At some point, if I were to swerve back and forth hard enough, something unpleasant would happen. But I'd have to really push it hard, even with my basic leaf spring axle setup.
When I did my first drive of both of my TDs, I took them out to wide open country roads and did some weaving and lane changes to see how they would react if I had to take evasive action. Could I make the kind of aggressive maneuvers that I could with no trailer behind me? No. But that was a simple matter of having a 600-700 pound trailer behind me, which would still be true if the trailer had a top-notch multilink suspension. If I have to make a sudden lane change, I am confident I could do it, but there is no doubt it will not be as smooth and easy as the same lane change with no trailer.
As far as the wife drifting back and forth in a lane, that is not going to create a sway problem, if you get the basics right, with axle placement being the most important basic. It may be annoying, but that little bit of change in direction is not dangerous.
I'd be more concerned about knowing what to do in an emergency situation. Going to a safe place, and practicing emergency maneuvers would be a much better use of time and effort than trying to make the perfect suspension for a TD build.