The latest descendant of the legendary military Jeep is a completely new Wrangler, built on a new frame, for 2007. And the new Wrangler is now joined by a four-door Unlimited model, with a back-seat designed to hold two adults or fold forward for increased cargo space. The Wrangler and Wrangler Unlimited are available in three models (Wrangler X, Sahara, and Rubicon), and all models have the same engine (a 202-horsepower, 3.8L V6) with either a six-speed manual transmission or four-speed automatic. The Wrangler still has solid axles, rugged recirculating-ball steering, removable doors with exposed hinges, a fold-down windshield, and removable soft tops, yet it has modern safety features like seat-mounted side air bags, ESP stability control, and four-wheel anti-lock braking. As in previous years, the Wrangler is available in many different configurations, appearances, and equipment levels, and can be everything from a reasonably comfortable road cruiser to a serious rock crawler. Most Wranglers have four-wheel drive, though the Unlimited model is available with two-wheel drive. The Wrangler's off-road ability has actually improved, with increased ground clearance and better wheel articulation than before, Dana axles, new electric axle lockers, and an electronic-disconnecting front stabilizer bar, called the active sway bar system (ASBS). Wrangler X and Sahara models get the second-generation version of Jeep's Command-Trac system, a part-time 4WD system with two-speed transfer case. A limited-slip differential is available. The especially rugged Rubicon model gets a Rock-Trac transfer case with a crawler 4.0:1 low range, along with front and rear axle lockers, Dana 44 axles, and serious 32-inch B.F. Goodrich off-road tires. The interior is considerably roomier than before, and more convenience features are available. Options now include power windows and locks, a full-screen navigation system, and a 368-watt, seven-speaker sound system with Sirius satellite radio. Several top arrangements are available, including a three-piece Freedom Top hardtop that can be removed and installed by one person, and a Sunrider soft top that includes a folded-back, 52-by-30-inch "sunroof" position in addition to the top-down position.