For 2003, Toyota redesigned its truck-based midsize sport-utility vehicle for the first time in seven years, giving it larger dimensions, new features, and its first available V8 engine. The 4Runner gained 4.5 inches in wheelbase and overall length, more than 3 inches in width, and 2 inches in height. Weight also escalated, by some 200 pounds. Despite the size increase, head and leg room remained about the same, though shoulder space and cargo volume grew slightly. Three models were offered: SR5, Sport, and Limited. Each seated five on front buckets (with height-adjustable driver's seat) and a split folding rear bench. No third-row seat was offered. A power tailgate window was again standard. A V6 engine also remained standard, but it was now a 245-horsepower 4.0-liter, instead of the previous 183-hp 3.4-liter. The optional V8 was the 4.7-liter, also used in Toyota's Sequoia full-size SUV, here tuned to produce 235 horsepower. While the V6 produced more horsepower, the V8 made more torque: 320 pound-feet, versus 283 for the V6. Both engines used automatic transmissions: a four-speed for the V6 and a new five-speed for the V8. The 4Runner came with rear-wheel drive or four-wheel drive. The V6's 4WD system could be left engaged on dry pavement, and V8 models got all-wheel drive. Both 4WD systems included low-range gearing. Traction control and an antiskid system continued as standard. Antilock brakes also remained standard, but with four-wheel discs instead of the prior disc/drum setup. Standard 16-inch wheels replaced 15s, made of steel rather than alloy. Sport and Limited models rode on 17-inch alloys. For the first time, the 4Runner was available with side airbags: a combination of front torso and head-protecting front/rear curtain side airbags. Other new options included a navigation system, rear-seat audio with wireless headphones, and a rear air suspension. Maximum towing capacity was 5000 pounds. With the 4Runner, Toyota competed against the Acura MDX, Ford Explorer, and Toyota's own Highlander. The 4Runner shared its platform with the new GX 470 from Toyota's Lexus division.