Stop differential movement and wheel-hop with polyurethane differential bushings. These bushings increase traction by keeping the differential properly located in the rear subframe. Under load from engine torque, the differential twists in its mount and distorts the factory bushings. When the tires begin to lose traction the load is released and the differential snaps back toward it’s original position. This shakes the whole suspension and contributes to a viscous cycle of loading and unloading, wheel hop, and loss of traction. These firmer bushings reduce differential movement, significantly reducing wheel hop. Fits 1999, 2001, 2004, 2004 Mustang Cobra 555-4015$41.95 www.realspeedauto.com Ph.631-563-7325 All parts listed are for the Ford Mustang unless otherwise noted. Copyright 2018 Realspeed Automotive Inc. All rights reserved.