New styling, new features, and more V8 power highlight the redesigned 5-Series for 2004. Gone is the wagon body style, leaving sedans that are slightly larger than the 1997-2003 generation. Four models are offered. The 525i retains a 184-hp 2.5-liter inline 6-cyl engine. The 530i carries over a 225-hp 3.0 inline 6. The 545i and 545i 6-Speed models use a 4.4-liter V8 with 325 hp, up from 290 in last year's 540i. All but the 545i come with a 6-speed manual transmission. Standard on the 545i and optional on the 525i and 530i is a 6-speed automatic with manual shift gate. Standard on all are ABS, antiskid/traction control, front side airbags, and front and rear head-protecting tubular side airbags. Rear torso side airbags are optional. Included on the 545i 6-Speed and optional on the other models is a sport suspension teamed with run-flat tires, plus BMW's Active Steering that electronically varies steering ratio and assist, and BMW's Active Roll Stabilization, designed to counteract body lean. All models have BMW's iDrive, which uses a console "joystick" knob to control entertainment, navigation, communication, and climate functions. Options include rear DVD entertainment, navigation system, front and rear park assist, heated front and rear seats, and adaptive cruise control designed to maintain a set following distance. Added midyear were optional head-up instrument display, satellite radio, plus, for all but the 545i automatic, sequential manual transmission. SMT is essentially a clutchless manual operated via console lever or steering-wheel paddles; it can also be set to shift like an automatic. BMW Assist emergency and concierge service and a tire-pressure monitor are standard.