Included with the Active Steering technology is BMW's Dynamic Drive active suspension system, (called Active Roll
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| My 545i tester cornered so prairie-flat, regardless of speed, that it was almost surreal given the 545i's respectable ride-quality. (Photo: Rob Rothwell, Canadian Auto Press) |
Stabilization in the U.S.) which utilizes active stabilizers in the front and rear suspension to minimize body roll when cornering. This hardware does just what the literature claims. My 545i tester cornered so prairie-flat, regardless of speed that it was almost surreal given the 545i's respectable ride-quality. And that's the dilemma that has stumped engineers since placing springs between the bodies and axles; how do you master pavement searing handling without resorting to injury-inducing spring rates? And then, if the ride is too harsh there's no travel, and therefore compliancy over bumps and dips, and a car that's first bottoming out and then flying through the air isn't exactly tractive. In addition to its active suspension technology, BMW has used an aluminum double-pivot strut-type front suspension and an aluminum 4-link integral rear suspension in the 545i.
BMW hasn't just pushed the envelope with its active suspension, they have licked it shut and mailed it. In so many ways the 545i delivers the virtues of a large comfortable sedan, sans ship-like handling. Toss the family-sized Bimmer into a corner and thanks to Dynamic Drive, it suddenly abandons its luxury-car aura in favor of M-car handling characteristics capable of tossing craniums side-to-side like a
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| BMW hasn't just pushed the envelope with its active suspension, they have licked it shut and mailed it. (Photo: Rob Rothwell, Canadian Auto Press) |
marbles in a pinball machine. There's something very satisfying and reassuring about knowing this level of agility exists in a car comfortable enough to satisfy the graying segment. In the all-Active 545i, swerves and curves can be approached with enthusiasm and complete driver confidence. This tenacious brute will hold a high-speed line like a lion holds its prey, only feeding back to the driver a slight amount of predictable understeer while controllably oversteering all day long if the electronic driver aids are switched off - but that's probably not a good idea unless you're a pro on a closed circuit course. If you do manage to push it too far with all electronics engaged and an imminent loss of control is detected, BMW's exclusive Dynamic Stability Control III will do everything modern technology can do to restore civility and frayed nerves.
