You may remember our Flexible Flyer buildup where we pretty much raved over the performance of our new TJ. When we wrote the feature, we had a great time shooting the photos and putting the Jeep through its paces for photography but, after spending more time with it, we found it had a problem.
It turned out that the air shocks we used in the buildup weren't really the hot setup for our application. Fox told us that the TJ was too heavy for the 2.0-inch air shocks used up front, as the 450 psi in them was over double the 200 psi they were designed to work with. We found that once we drove the Jeep for a while, the shocks would rebound, or extend too quickly. On acceleration, the nose of the Jeep would shoot to maximum extension, and then slowly return to static height. This was on a Wrangler that had long Moab 4x4 Outpost arms with the correct geometry that would keep the nose down under normal conditions. Fox said it could build more rebound damping into the shocks, but with the pressure we were running, they'd never work as we wanted them to. The company suggested we switch to its 2.0-inch coilover that had the same dimensions as the air shock. We agreed. We also decided to take the Wrangler to the next level and build it into one of the finest dual-sport TJs around.
To do this, we enlisted the help of Kevin Hawkins of Salt Lake City, Utah, to "Kevinize" our TJ. Kevin has been our off-roading friend for years and builds some of the finest Jeeps and trucks on the planet in his spare time. A contractor by trade, Kevin is as picky as we are, is a great fabricator, and knows suspensions.
The first thing Kevin did was to install the Fox 2.0 coilovers with coils that had 275-pound primary and 400-pound secondary rates. After doing this, he decided to install Fox 2.0x5/8-inch emulsion shocks in the back to get more travel and complement the front. As anyone who's built a TJ knows, it's hard to get a longer shock under the body without laying them down. Kevin found enough room outside the frame to mount the 2.0-inch shocks there. This not only allows a longer shock to be used, it also adds stability to the Jeep.
After installing the rear shocks, the Wrangler was driven fairly hard. The first thing that came to light was that the front coils were too stiff. We called Eibach and had no luck, as it has the very worst customer service on the planet. Just as we were going to go elsewhere to get coils (which was a shame since Eibach coils are superb), we found that Parker Pumper, builders of the famous race helmet filtration systems, is also Eibach's largest coil spring dealer. When you go to its website and click "Search," you're taken right to the spring order page where you can get just about any size or rate coilover spring you need. The company will even exchange a coil if you order the wrong one and figure it out before marring it! Parker Pumper's great service makes up for Eibach's dismal customer service. So, Kevin replaced the 275-pound primary coil with a 225-pound one and the 400-pound secondary coil with the 275-pound one. Spring rates and valving were now perfect up front, and the nose no longer pointed to the sky under acceleration or climbing.
To make all four corners of the Jeep adjustable, Adjustable Coil Over Spacers (ACOS) from JKS Manufacturing were installed in back. Along with Currie variable-rate coil springs and bumpstops, the rear is also completely adjustable and sits perfectly.