King Coilover Shock Tuning
Suspension progression is part of the off-road hobby. For those looking to go fast off-road, a well-tuned suspension is a necessity. For those simply searching for a better ride quality on- and off-road, it’s an investment in comfort. One of the most common and sought-after suspension upgrades is moving to coilover shocks. The reason is simple.
Unlike a leaf-spring or standard coil and spring configuration, a coilover can be easily tailored to fit your rig and driving needs. By swapping coils, valve packs, and adjusting the position of the shock itself, you can create a suspension that can handle virtually all of your off- and on-road needs. While coilovers have been a staple in the competition side of the off-road industry for years, the recreational side of the hobby has only more recently adapted the coilover as a suitable suspension member for a daily driven vehicle.
Bolt-on coilover kits and complete coilover conversion systems have changed the way we view the coilover and ushered in a new benchmark for what it possible with a daily driven 4x4. The biggest draw to the coilover for us is the fact that we can tune it with relative ease. Take for example our heavily modified ’97 Jeep Wrangler.
For nearly a year, the V-8–powered TJ has used King 2.5 coilover shocks up front. While King was able to get our shocks in the ballpark when we ordered them originally, we knew we’d likely need to fine tune the shocks later down the line. With a few thousand miles under our belt, we were able to establish that we needed a bit more compression valving for our more spirited off-road driving.
So, we ordered a new set of valves from King and decided to tear into the coilover. While we could have sent our shocks out to King to have this done, we knew that this can be easily accomplished from the comfort of our home garage. In fact, breaking down the King shock didn’t require any specialty tools, just a little knowledge, a bench vise, and a couple hours of time.
Since we’ve been working on our Jeep Cherokee XJ project (Disposable Hero) at Low Range 4x4 in Wilmington, North Carolina, we decided to stay late one afternoon and pull our TJ in to knock out the shock rebuild. The following procedure can be used for most 2.0 and 2.5 King shocks. This includes bypass shocks, as well as standard, smooth-body, non-coilover shocks.
There is often a bit of misconception about the importance of a fluid reservoir. In a non-reservoir nitrogen-charged shock, the valve piston and floating piston are housed in the same cylinder. This more condensed setup leaves less room for fluid, along with a smaller nitrogen pocket. This setup can impede the travel of the shock as everything has to occupy the single cylinder.
With a reservoir shock, the shock internals are more spread out. The two major advantages of this are, one, that the shock shaft can be longer without requiring a longer body on the shock. This means you can fit a longer travel shock in a smaller space. The second major advantage is fluid distribution. As your shock cycles, it creates heat. As the temperature of the fluid increases, the effectiveness decreases. So, by adding a fluid reservoir you can prolong the negative effects of heat.