5. Another aspect of the J-Spec system we liked is the custom-tuned Bilstein piggyback shock absorbers. JKS partnered with Bilstein to fine-tune these 5150-Series shocks for a perfect balance of on-road stability and rough-terrain damping. The bar-pin eliminators shown here are the cat's meow because they are super-easy to install, and much stronger than the factory stamped type. Additionally, they compress the bushing sides to eliminate noise and premature wear caused by distortion.