Lexus redesigned its midsize sedans for 2006 with more power, fresh styling, and new features--including available all-wheel drive. Compared to the 2001-2005 version, the GS gained 2 inches of wheelbase and measured an inch longer overall. The rear-wheel-drive GS 300 and the all-wheel-drive GS 300 AWD had a 245-horsepower V6 engine. The rear-drive GS 430 held a 300-horsepower V8. All models used a six-speed automatic transmission with manual shift gate. Antiskid/traction control and antilock four-wheel disc brakes were standard. The GS 430 added driver-adjustable shock absorbers with three firmness settings. GS 300s rode on 17-inch wheels; the GS 430 used 18-inchers. Run-flat tires were standard with AWD, optional otherwise. All models had front knee airbags, front torso side airbags, and head-protecting curtain side airbags. Also standard: a keyless-entry/engine-start system, hands-free wireless cell phone connection, leather upholstery, and heated power front seats. An information touch screen displayed an available voice-activated navigation system, rearview TV camera, and with the transmission in Park, DVD video. Other options included cooled front seats, front/rear-obstacle detection, and steering-linked headlamps. Also available was Lexus' Pre-Collision System, designed to automatically cinch seatbelts and apply brakes if an unavoidable crash was detected. With its GS sport sedan, Lexus competed against the BMW 5-Series, Infiniti M, and Mercedes-Benz E-Class. A gas-electric hybrid version, called the GS 450h, went on sale in early 2006. It teamed a gasoline V6 engine with an electric motor to produce a total of 339 horsepower. Like other Lexus and Toyota hybrids, the GS 450h could run on either gasoline or electric power, or both sources, depending on conditions. No plug-in charging was required. A continuously variable transmission (CVT) worked with the GS 450h.