Coilover shocks are complex components, but tried-and-true and a common sight on a well-built trail rig. Manufacturers have gotten the damping characteristics of these high-tech shocks down to a science. Coilovers can be ordered with close-to-optimal ride qualities for the conditions you want to wheel in. Setting a custom 4x4 up with coilovers may be more difficult when it comes to figuring out the proper spring rate and valving. The factors can be determined by trial and error or by a slightly more scientific approach.