After 5 years of development and over 100,000 test miles, our Heavy Duty Adjustable Jeep JK Ball Joints are here! This is the last set of ball joints you will ever have to buy. Limited Lifetime Warranty. Tighten up your steering for good with our patent-pending (# 16/020894) design which is fully adjustable, serviceable, and rebuildable without having to press the ball joints back out of the axle end forging yokes (C's). These ball joints never have to come back out. Available in knurled and non-knurled versions to fit all vehicles regardless of what type of ball joints were installed previously. Lower ball joint bearing surfaces are CNC machined from 4140 steel, heat-treated, induction hardened, and ferritic nitrocarburized to make these the longest-lasting, longest wearing ball joints on the market. Kit includes all 4 ball joints to service one Jeep and the adjuster tool for adjusting the preload on the lower ball joints.