Yukon Powr-Lok replacement race positraction for Dana 44 with 30 spline axles. fits 3.73 and down. Will chatter. The Powr-Lok is one of the most aggressive and strongest limited slips ever designed. It uses a two-piece case and six forged internal gears for added strength. The Powr-Lok uses a ramping-clutch design to become more aggressive as tire-spin increases. The composite clutches provide long life and high performance. All units are Rebuildable and come with a one year warranty against manufacturing defects.