Originally Posted by Westcliffe01
I have thought of using a short mount for the leading edge of the spring and a long one for the back, to try to keep the spring movement perpendicular to a line from the axle
to the center of the hitch ball.
I see the logic, but I wouldn't do that.
When a beam axle
on a leaf spring moves vertically, it also moves forward or backward slightly. When it tilts (because the vehicle is leaning such as in a turn or sway oscillation), the difference between left and right vertical travel causes different fore/aft movement... that means the axle
steers. If the front mount of the spring is lower than the rear, it steers into the turn, which is good for stability; that's why trucks have their rear leaf springs noticeably sloped front-down.
Longer mounts on the rear would slope the springs the wrong way for stability. I suspect that just shocks would make a significant difference.