The mid-size 2011 Nissan Frontier pickup comes in two cab styles--King Cab and Crew Cab. The King Cab has smaller, rear-hinged rear doors and the Crew Cab has full-size, front-hinged rear doors and a larger rear-seat area. The King Cab is available in a single bed length, while the Crew Cab is available in standard bed and long bed versions. The Frontier shares its basic layout, including the suspension and other components with the larger Titan pickup. This setup includes a double-wishbone front setup with a solid-axle and leaf springs at the rear. The base S and SV Frontier King Cab rear-wheel drive trucks feature a 152-horsepower, 2.5L 4-cylinder engine. All other Frontiers are powered by a 4.0L V6 engine, making 261 horsepower and 281 lb-feet of torque. This predominantly aluminum, double-overhead-cam engine utilizes continuously variable valve timing, variable induction and a number of technologies to ensure smooth operation and efficiency. Four-cylinder models have a 5-speed manual transmission standard, while V6 models get 6-speed versions. A 5-speed automatic is available on both. On V6 models, a 4-wheel-drive system is available which features electronically controlled shift-on-the-fly engagement and a low range. The 4-wheel drive models also bring a 4-wheel limited-slip system. Hill Descent Control is a system intended to help maintain a steady, slow speed while descending especially steep slopes, while Hill Start Assist allows a smooth, controlled start on a steep incline without roll-back. Both features are standard on all 4-wheel drive models and an automatic transmission. The top-of-the-line SL includes the V6 engine and 5-speed automatic transmission, as well as additional features such as 18-inch aluminum wheels, fog lights, 8-way adjustable power driver's seat and side step rails. For the off-road enthusiast, Nissan offers the PRO-4X edition, which is available in both the King Cab and Crew Cab SV V6-equipped Frontiers with either rear-wheel or 4-wheel drive. The package brings Bilstein performance shocks, an electronic-locking rear differential and anti-lock-brake-controlled limited slip. The PRO-4X also includes additional skid plates and 16-inch off-road tires. The Frontier has several innovative storage options, including storage boxes under the rear seats, a large center console, a dual-compartment glove box and several power points. The Utili-Track system, which brings removable utility tie-down cleats and secure attaching channels, is available and especially useful for securing heavy cargo that doesn't take up the entire bed. Front-seat side air bags are standard, as are side-curtain air bags that cover front and rear occupants and stability control is standard on V6 models.