We call it "crawling" for a reason. Use a low gear and low-range 4WD and just let the vehicle crawl and idle (with as little throttle as needed) when going over obstacles like rocks or logs. Never straddle rocks. A vehicle with 10 inches of ground clearance will not go over a 12-inch rock! Maneuver the tire on top of the rocks and crawl over them slowly. If you hear scraping, don't panic. Your Jeep 4x4 vehicle's skid plates and rock rails (this equipment varies depending on what Jeep 4x4 vehicle and packages have been purchased or leased) will take the brunt of the beating. Dropping tire pressure 3-5 pounds improves traction and helps avoid tire punctures. (Return to normal pressure after use in these conditions.) Remember, the ideal speed for rock crawling is 1-3 miles per hour.