The BMW 5 Series undergoes numerous changes for 2006, including several new models or model designations. The series now consists of the 525i and 525xi sedan; 530i and 530xi sedan; 530xi Touring (wagon); the 550i sedan; and the high-performance M5 sedan. The 550i is a model designation update from 2005’s 545i; the xi designation means xDrive, BMW’s all-wheel-drive system.

Changes include new, higher-output six-cylinder engines; a 4.8-litre V8 replaces 2005’s 4.4-litre in the 550i; and the new M5 features a lightweight V10 engine. All 5 Series models receive Servotronic speed-sensitive steering, and Dynamic Stability Control gains hill-start assist, brake standby to reduce stopping distances in an emergency, brake drying, fade compensation, and “soft stop” for smoother stops and reduced brake dive. Inside, the 5 Series receives a start/stop ignition button originally found on the 7 Series, and a revised iDrive controller. On the 530 Touring, the Premium Package option includes a Storage Compartment Package that adds an extendible rear storage base unit.

The 525 and 530 models both use a 3.0-litre inline six-cylinder, mated to a six-speed manual transmission that can be optioned to a six-speed automatic with Steptronic manual mode. In the 525, the engine makes 215 hp; in the 530, it’s tweaked to 255 hp. The 550i uses a 4.8-litre V8 that makes 360 hp, while the awesome M5 carries a 5.0-litre V10 that spins out 500 hp and can travel zero to 100 km/h in 4.7 seconds, on its way to a top speed of 250 km/h. It exclusively uses a seven-speed SMG transmission, a sequential gearbox that is shifted via a lever on the centre console or wheel-mounted paddles; it can be set at one of eleven gear change options, from completely manual to completely automatic.

Standard or available features on 5 Series models include drive-by-wire throttle system, automatic and adaptive Xenon headlights, headlight washers, tire pressure warning system, interior motion sensor alarm, twin chrome exhaust tips, heated multifunction steering wheel, automatic air conditioning, ten-way power heated seats, power sunroof, “leatherette” or Dakota leather interior, CD/MP3 stereo, BMW Assist with emergency button, telephone preparation, and iDrive system.

The M5 includes an “M Power” switch for more progressive throttle response, oil quality sensor, M5-specific sport suspension calibration, oil supply with lateral force control, M-specific front spoiler and fender gills, twelve-way power sport seats, Merino leather interior, Alcantara roof liner and six-CD/MP3 player.

Models with xDrive use a torque-management system that switches seamlessly from rear-wheel to all-wheel-drive when necessary. Unlike many AWD systems that distribute power when one set of wheels slips, xDrive is proactive, using information from the dynamic stability control and other sensors to determine the possibility of wheel slippage and the need to power up or brake a specific wheel, before any wheels actually start to lose traction. It also locks the differentials on take-off until the vehicle reaches 20 km/h for maximum traction.

The larger line-up makes the 5 Series an attractive choice, especially in the functional Touring configuration. All are smooth, powerful drivers, especially with the 2006 power increase. The M5 remains the epitome of the series, offering Dodge Viper horsepower (although with less torque) with refined manners and a lower price.

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