Finally, 4 Wheel Parts greaseable leaf-spring bolts were installed. These polyurethane bushings are fluted to hold lube, and the through bolt is drilled and fitted with a grease zerk. These didn’t increase axle articulation, but the stock rubber bushings were shot so the new bushings greatly improved axle control. On the rear of this truck, the bolts hit the shackle hanger at full droop, but trimming the bolt didn’t improve the RTI results. Our final improvement on the ramp came through removing the overload spring on the bottom of the Genuine Suspension rear leaf springs. This lowered the cargo-carrying capacity of the truck, but made a significant difference in wheel travel.