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Wishbone bushings mounted in opposite sides of frame rails counteract each other force/torsion?

Wishbone bushings mounted in opposite sides of frame rails counteract each other force/torsion?

Wishbone bushings mounted in opposite sides of frame rails counteract each other force/torsion?

(OP)
In the sketch the frame rail is red, wishbones are blue, wishbones bushings are mounted in the green transverse brackets mounted in exact opposite directions from each other, aligned with the frame rail center point.

Will this setup mostly cancel resulting frame rail twist along its longitudinal axis?

Of course the spring is missing but lets suppose it will create little or no frame twisting.


RE: Wishbone bushings mounted in opposite sides of frame rails counteract each other force/torsion?

No, nor do I think there is any possible way to do it, for the simple reason that the tire contact patch is below the frame rail (has to be, unless you want to be dragging the frame rail on the ground), and lateral forces will therefore always apply a twisting force to the frame rail.

Think about it. Picture a force being applied rightward at the tire contact patch and the frame rail is therefore pushing leftward (from the inertia of the rest of the vehicle). The lower control arm is being compressed and the upper control arm is being pulled. Therefore, there is a twisting action being applied to the frame rail. There is no getting around it.

RE: Wishbone bushings mounted in opposite sides of frame rails counteract each other force/torsion?

Really, any arrangement of links or brackets will still apply an equal torsion to the frame rail, regardless of the link and bracket arrangement chosen. No matter the connection, from linked suspensions to torsion bars to a rigid connection, you still have a vertical force at the tire with a moment arm equal to the horizontal distance between tire and frame rail.

The only way to avoid frame rail torsion at the suspension attachment is a frame crossmember to the opposite frame rail. The crossmember will then take the moment in bending, and you will eliminate most of the static torsion in the frame rail. Or, obviously, a solid axle with leaves directly under the frame rail, but I doubt that's what you're looking for. smile

Chuck

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