Powerflex PFR5-3608B Black Series Rear Trailing Arm Front Bushings Powerflex polyurethane replacement Rear Trailing Arm Front Bushings. Set of 2. PFR5-3608Bx2 This part is suitable for street or track use. Purple/street bushings are not offered for this location. All Powerflex products come with Manufacturer's LifetimeWarranty! Powerflex copper-based grease is supplied with every bushing set Powerflex Black Series