3 link suspensions place excessive loads on the upper link bushings. In the '05, two bushings are responsible for handling the same torque load that 4 bushings had done before. Additionally, these bushings are subjected to more "twist" than before since the rear end can better articulate as a 3 link design. In order to allow free articulation, the OE rearend bushing is designed to flex. This flex is great for handling but under straight line acceleration, it contributes to wheelhop and inconsistant launch characteristics.
Energy Suspension offers a no-compronise solution with it's dual durometer 5 piece polyurethane replacement bushing. By designing the bushing as a multi-piece unit, it allowed them to keep the inside portion stiff for great straightline acceleration load and the outside portions soft for bind-free handling. NOTE: requires use of existing bushing shell