Jeep Wrangler Rubicon Hummer H1 Land Rover Range Rover HSE Mercedes Benz G55 AMG Lexus GX 470 Nissan Titan Hummer H2 SUT Front View

The Ultimate 4x4 Challenge: Jeep Wrangler Rubicon, Hummer H1, Range Rover HSE, M-B G55 AMG, Lexus GX 470, Nissan Titan, Hummer H2 SUT

Off the Road
Our first event of the day was running over the "Frame Twister," aptly named because of the strategically placed logs criss-crossing a narrow path, finishing up with several deep, off-camber water holes. Earlier, we had measured all our vehicles on our custom-built 18-degree ramp to see what kind of Ramp Travel Index each one could achieve. We found the Jeep and Lexus (our two shortest wheelbases) to have the best scores. But that score is not an infallible predictor. Each of our first three vehicles that attempted the Frame Twister had to be yanked out with the Hummer H1's heavy-duty winch. Of the three, the Wrangler Rubicon did the best because it was able to skirt along the edge of the logs and not dip a tire into the goopy slop. Apparently, the night before, the Rangers thought it would be funny to soak the Frame Twister with water, creating a type of bottomless quicksand between each of the logs. Actually, it turned out to be a mud-throwing good time as we positioned the H1 ahead of the obstacle and winched most of the trucks through. Near as we could tell, we didn't bend a single frame or break any parts (sidesteps are another story).

Next came the hillclimb--the steepest trail in the park, and we needed to get all the vehicles up it to tackle our next trail. One at a time, our fearless test drivers locked their rigs into low-range and first gear, then headed up the face. (Editor's note: One of the many tragedies in automotive magazine journalism is that it's incredibly difficult to get a photo that shows the reader how steep something is.)

This obstacle basically comes down to gearing and tire choice. In some cases, depending on the grip you can get on a hillclimb, airing down can help give you more tire surface area to claw at the earth. Mud tires seem to work well, and so does extra weight pushing down on the tires. For that reason, the ultra-low-geared (63:1 crawl ratio and knobby tires) Wrangler Rubicon and Hummer H1 (7200 pounds with 37-inch deflatable tires) had the easiest time up the mountain. Five of our competitors had crawl ratios right around 33:1 (about standard for good 4x4s), with much of that determined by the low-range gear in the transfer case. A typical low-range is between 2.56:1 and 2.72:1. The special Jeep Wrangler Rubicon package offers a 4.00:1 low-range.