Lexus added a third luxury sport-utility vehicle for 2003, to fill the gap between its car-based RX 300 and truck-type LX 470. The GX 470 shared a new body-on-frame design with the redesigned 2003 4Runner from parent company Toyota. Its V8 and five-speed automatic transmission also were found in the 4Runner, as well as the 2003 LX 470. So was the standard all-wheel-drive system, with low-range gearing and a locking center differential. Unique to the GX was Lexus's new Downhill Assist Control, which automatically applied the brakes to limit speed down steep grades. Also included was Hill-start Ascent Control, which could hold the vehicle in place on an incline for five seconds. Standard features included 17-inch wheels, antilock four-wheel disc brakes with full-power assist, and an antiskid/traction control system. In addition to front torso side airbags, the GX 470 had curtain side airbags for the first two seating rows. Also included were a self-leveling rear air suspension, height-adjustable suspension, and automatic shock-absorber control within four driver-selectable modes. Further imitating big-brother LX were standard leather upholstery, automatic climate control, an in-dash CD changer, driver-seat memory system, and lighted running boards. Unlike 4Runner, the GX 470 offered a third-row bench seat for up to eight-passenger capacity, the same as the LX. The GX had a swing-open tailgate with fixed glass, versus the 4Runner's liftgate with power-opening window. Options included a navigation system, premium Mark Levinson audio, heated front seats, rear air conditioning, and a rear DVD entertainment system. A sunroof and rain-sensing windshield wipers also were available. Maximum towing capacity was 5000 pounds (6500 with the optional towing package). GX rivals included the Acura MDX, Cadillac SRX, and Mercedes-Benz M-Class.