The 2008 Nissan Xterra is powered by a 261-horsepower, 4.0L V6 engine and either a six-speed manual or five-speed automatic transmission. Each model (except for the Off-Road model) is offered in a choice of rear-wheel drive or a four-wheel drive system that has an electronically controlled part-time transfer case with low-range mode. The engine has a modern aluminum-block design, supplemented with cast-iron cylinder liners, Teflon-coated pistons, variable induction, variable valve timing, and a two-stage timing chain for durability and smooth operation. The Xterra has serious truck underpinnings good for off-road adventuring, hauling heavy loads, or towing up to 5,000 pounds. Its so-called F-Alpha platform and fully-boxed frame is shared with Nissan's Titan and Frontier pickups, along with the Armada and Pathfinder SUVs. In front, the suspension is an independent double-wishbone design with a stabilizer bar, while there's a heavy-duty solid-axle setup with leaf springs in back. Off-Road models are supplemented with Bilstein gas shocks, which are comparable in on-road control but offer more wheel travel. With its many utility-oriented features, the Xterra is ideal for especially active people who carry heavy gear and need to go off-road. Side steps are built into the rear bumper for easy access to the roof rack, which has a latchable lid. The cargo area has an Easy Clean surface and ten cargo utility hooks, including six floor hooks capable of carrying up to 110 pounds each. In addition there's an available adjustable channel system in the cargo floor, similar to that offered in Nissan pickups, for securing bike racks or specialized gear. There's also space to secure and carry jugs of up to a gallon. Very short front and rear overhangs make the Xterra well proportioned for off-roading. It has several specialized features oriented toward rough terrain, including hill descent control and hill start assist, which both increase safety and help maintain control on steep slopes. Off-Road models include those two features plus an electronic-locking rear differential. Safety features on all Xterra models include front-seat side-impact air bags, electronic stability control, and anti-lock brakes. Roof-mounted side-curtain air bags, which cover all outboard occupants, are optional. Four different models are offered: X, S, Off-Road, and SE. The base X model includes keyless entry and power windows, locks, and mirrors, while the S adds step rails, a first-aid kit, a cargo net, roof-rack cross bars, a gear basket, upgraded seat fabric, alloy wheels, the Easy Clean cargo surface, and a C-Channel cargo floor. Stepping up to the Off-Road model bring the aforementioned off-road equipment, Bilstein shocks, off-road tires, skid plates, fog lamps, black bodyside molding, a fold-flat passenger seat, blue cloth seat fabric, and a leather-trimmed steering wheel. At the top of the range, the SE gets a standard automatic transmission, plus Long Trail tires, body-colored exterior mirrors, a Rockford Fosgate premium audio system with six-disc changer and auxiliary input, and steering wheel audio controls.