I asked why this setup , The primary purpose for the air shocks that hooks from the trailing arm to the axle eliminate the need for upper link arms, The benefits that came from these air shocks are: holding the axle in place, allowing the air shock plunging into itself under articulation make the movement possible and the resistance that comes from this now acts as a sway bar helping with dirt/street control.

They also make the standard 4 link, but he likes to use his axle set up


They also make the standard 4 link, but he likes to use his axle set up
