You may remember Project TrailRunner, the yellow 2008 Jeep JK Wrangler Rubicon that we built to work on the trail (Trail) and go fast in the dirt (Runner) with very little suspension lift.
TrailRunner worked fine. Our October 2010 Garmin GPS feature had a photo showing "Maximum Speed - 91 mph" shot in the dirt in TrailRunner. Our policy here at the magazine is, "If it works, change it," so we put it on the hoist at Impulse Off-Road and started removing parts.
As we've mentioned more than a few times in the past few months, a 4x4 doesn't have to be equipped with 44-inch tires and no fenders to be a capable off-road vehicle. In my case, I have to drive these projects as daily drivers and the "sleeper" builds work better. With this in mind, John Williams and I had a plan for TrailRunner.
The Xenon flat flares still looked OK after three years, but we replaced them with the TrailRunner's original OE fender flares and liners that I had stored in my shop when we originally built the Jeep. The OE flares work better at keeping mud off the windshield at higher off-road speeds. Going back to OE flares meant that either taller coils or smaller tires were required. I didn't want to change the lift. The 2.5-inch TeraFlex coils work well and the Jeep exhibits no driveline vibration. Thirty-five-inch tires were the answer. The 35s are much lighter than 37s (or larger). Less unsprung weight improves a 4x4's performance. It surprises many how well 35-inch tires perform on the trail. They should, as most of today's non-buggy trails were originally built using vehicles with 35s, 33s, or even smaller tires. Going to smaller tires called for a gear change. John expertly replaced our 5.38 gears with Yukon 4.88s.
JK shock technology has improved greatly in the last three years. For TrailRunner's rebirth, the Elka shocks had to go. They worked OK three years ago when compared to other shocks we tried, but they don't compare with shocks available today. That, plus the fact that two of the Elkas were leaking, "sealed" the deal and we're finding new shocks for TrailRunner.
Our bumper and winch system included a beefy front bumper and heavy Warn PowerPlant HP winch. It's great to have the big, fast Warn air compressor up front out of the way, but I want TrailRunner to shed some weight. To this end, we installed an Expedition One Basic DX bumper with foglight wings. The bumper with the wings is lightweight. I replaced the PowerPlant with a Warn 9.0Rc rock-crawling winch that weighs only 54 pounds. It's OK, but if we can get a Warn Zeon to fit, I think I'll like that better. The Zeon 10-S weighs 69 pounds, still much lighter than the PowerPlant. After it's finished, we'll have shed at least 80 pounds from the front of the Jeep.
I have never liked the Yes Essentials fabric that came in Jeeps from 2007 to 2010. It stained easily, trapped dirt, and didn't look that great. Hot Head Headliners now offers Hot Head Seat Covers for the JK. They slip on over the OE fabric and are available in leather, vinyl, or a combination of the two. I chose quality black leather covers that are easy to clean, look and feel better than original equipment leather, and are much better than the OE fabric on TrailRunner's seats.
To a casual observer, TrailRunner looks milder than it did before. Performance-wise, the Wrangler is getting better than ever. One more change is in the offing. While the 3.8L V-6 is a reliable mill, there's an engine swap in this JK's future.