2011 BMW 5 Series sedan

Other big changes include the 5 Series' new electric-assisted steering and its boosted engine power. The steering gets mixed reviews -- it's certainly precise, but Car and Driver testers say it feels too light, and Edmunds.com says it's not as engaging as the 3 Series'. The new engines get a better reception. The base 240-horsepower, 3-liter straight-6 on the BMW 528i (Base MSRP $44,550) packs plenty of power in tests, and its 25 mpg combined (22 mpg city/32 mpg highway) make the 528i the most fuel-efficient luxury sedan you can buy, according to FuelEconomy.gov. This trim level comes with an eight-speed automatic transmission with manual shift control.

The BMW 535i (Base MSRP $49,600) turbocharges the engine for 300 horsepower and comes with a six-speed manual transmission, dropping fuel economy to 19 mpg city/28 mpg highway, according to BMW (with the optional automatic, the Environmental Protection Agency estimates you'll get the same gas mileage, an average of 22 mpg combined). Unlike its former twin-turbo engine, the new 535i uses a single twin-scroll turbocharger. Autoblog.com says this engine "just plain works, with eager revs and a wonderfully flat power curve." Car and Driver detects no turbo lag or whine. TheTruthAboutCars.com's Karesh does notice "more lag and more of a boosted feel" than with the old engine at low rpm, but it's "a very quick car nevertheless."

The BMW 550i (Base MSRP $59,700) substitutes a 400-horsepower, 4.4-liter, turbocharged V8 that Car and Driver calls "ridiculously" powerful. Its fuel economy drops to 20 mpg combined (17 mpg city/25 mpg highway) with the automatic transmission, plummeting to 17 mpg combined (15 mpg city/22 mpg highway) with the manual. All-wheel drive is an option on the 535i and 550i.

Critics like the 5 Series' clean, ergonomically sound five-passenger cabin. "Leatherette" vinyl upholstery comes standard except on the BMW 550i, which has leather seats. Testers find the seats comfortable, with class-consistent backseat room -- "enough room for a pair of 6-foot adults to be comfortable," Edmunds.com says, although the 14-cubic-foot trunk is a little small for its class.

The BMW 528i and 535i include a moonroof, 10-way power front seats with driver memory, automatic wipers, heated side mirrors, dual-zone automatic climate control, Bluetooth, the iDrive controller for cabin electronics (which critics say is vastly improved over previous years) and more. The BMW 550i adds better front seats and leather upholstery, parking sensors, a voice-controlled navigation system and a few other features that are optional on the lower models. A slew of high-tech add-ons are available, including active four-wheel steering, active cruise control, cameras surrounding the car, a night-vision system, an automatic parking feature and systems that warn you if someone's in your blind spot, you're getting ready to rear-end someone or you drift out of your lane.

The 2011 BMW 5 Series gets perfect crash ratings at the Insurance Institute for Highway Safety. It had not yet undergone federal crash testing when we checked. Standard safety features include antilock brakes, traction and stability control, and front, front-side and curtain airbags.

This new model has no reliability history yet. The 5 Series carries four-year/50,000-mile basic and powertrain warranties.

Research sources

Edmunds.com tests the 2011 BMW 5 Series and reviews all of its trim levels in detail. Car and Driver, TheTruthAboutCars.com, The New York Times and Autoblog.com all test one or two 2011 5 Series trim levels apiece. We found crash ratings at the Insurance Institute for Highway Safety and fuel-economy estimates at FuelEconomy.gov and the BMW website.