2015 Buick Regal

The doors have glints of metallic trim and sweeping lines that read upscale, and on GS cars, the white-stitched black leather seats do the same. Regal owners can choose from satin metallic interior trim, piano-black plastic or a dark wood called Kibo; we come down in favor of the satin trim, which doesn't date the cabin or leave it smudged with fingerprints.

The pings of the past are few: the Regal has a waterfall grille, and the 19- and 20-inch wheels are more a concession to old-school American taste than to modern-day handling and engineering. The Nike-like swoosh pressed into the doors is the telling detail: the Regal may be the best-looking four-door GM has in its stable today,  still a knockout, trimmed out even better with LED "wings" factored into its headlamps and taillights for the new model year, along with a retouched grille and a metallic band that connects the taillamps.

The GS' front end is broken up with bladed, vertical air intakes. In back, the exhaust tips are reshaped, and the small decklid spoiler is a bit larger.

The Regal GS is still the version we'd choose, every time. It gives the Buick brand a new benchmark for precision, without falling over itself in homage to Germany's sport sedans (though at heart, it is one--it's based on GM Europe's Opel Insignia sedan).

The Regal GS may not have its own stand-alone engine this time, but it has some carve-outs to call its own. The manual transmission now is limited to the Regal GS, and so is the three-mode Interactive Drive Control, which changes the responsiveness of its adaptive dampers, of the throttle and transmission and even steering feel. It continues to ride on a lowered suspension with beefier front struts, and on standard 19-inch wheels with all-season tires, while 20-inch summer tires are available.

It's still a bit notchy, with just enough foot space to the left of the third pedal for wide feet, but the Regal GS' manual shifter connects well with the turbo four. The automatic goes without paddle shift controls, so no matter which one you pick, you'll be moving a hand from the wheel to change gears. If you're shopping for all-wheel drive exclusively, you'll have to take the automatic, and the slightly redesigned rear suspension.

With either transmission, the Regal GS has a wider range of handling, and clear levels of resolution between the three driving modes. Out of the gate, the "Touring" mode is soft enough for any daily driver, but handles flatter and more cleanly than the base turbo.  Even in Sport mode, the Regal GS doesn't tighten up in any unreasonable way.

By the time it's progressively tightened up to the GS setting, the Regal still behaves in a way both of its names imply, while it tightens its reflexes to a sporty degree that's acceptably shy of the true sports sedans from BMW, Cadillac, and others. The Regal GS omits the overly heavy steering, the crazy-quick throttle of some of those cars, but doesn't have their nine-tenths precision, either. All-wheel drive amplifies the car's composure over scrubby pavement; the GS' big disc brakes have a reassuring bite, too.

Regal eAssist: too mild a mild hybrid?

There's also an electrified Regal, the one outfitted with GM's mild-hybrid eAssist drivetrain. It returns for 2015, and it still suffers a fuel-economy penalty and a smoothness deficiency against most full hybrids in its class. The eAssist neuters what we like best about the latest Buick Regal--its supple ride and capable electric power steering.

The eAssist basics include a 2.4-liter, 182-horsepower four-cylinder engine, paired with a six-speed automatic transmission, lithium-ion batteries and an electric motor. The electrification pieces can't power the Regal by themselves; instead, GM uses them to run ancillary systems like the oil pump, and to contribute torque to the Regal's drivetrain. The lithium-ion batteries recapture brake energy to recharge, and also draw a little engine torque to do the same.

In our recent test drives, the eAssist drivetrain performs well enough in other applications, such as in the Buick LaCrosse. In the Regal eAssist, the numbers and smoothness don't seem to justify the performance penalties. The Regal eAssist grabs and hitches as it seeks to hold on to all the available regenerative energy from the electric motor; the switch from regeneration in the motor to the Regal's friction brakes is obvious. It also rides on 17-inch, low rolling-resistance tires, and they lack the precise feel imparted to the other Regals. The eAssist is rated as high as 25/36 mpg on the EPA cycle, but we've seen only up to 29 mpg in mixed driving. A Nissan Altima is EPA-rated at 38 mpg highway; a Ford Fusion Hybrid, at 47 mpg, in which we've earned an easy 41 mpg. 

Regal Turbo

None of today's Regals have a V-6, much less a V-8, but the new turbocharged four-cylinder that's standard on all non-eAssist Regals is a sweet-revving engine that generates strong acceleration.

Both the Regal Turbo and Regal GS now get a single turbocharged 2.0-liter four-cylinder to replace last year's last-gen turbo four, which was offered in 220-hp and 270-hp spec. The new turbo's related to the one found in the Chevy Malibu and Cadillac ATS, with a twin-scroll turbo and direct injection.

There's no longer a distinction between the two in output, however: Buick's settled on a single quote of 259 hp and 295 lb-ft of torque, down 11 hp from the last GS but up 39 hp in the Turbo. Buick says 90 percent of peak torque is available as low as 1700 rpm on the GS, and says 0-60 mph times should be identical to last year's model, at well under 7.0 seconds. On the mid-line Regal, the turbo four comes with the same six-speed automatic as before.

In our first drive, this Regal turbo's undisturbed by the powertrain transplant. It remains a composed, quick performer with mainstream moves. It's muted well to near-redline revs, and as usual, GM's automatic clicks off shifts as well-damped as the Regal's ride. GM's new electric power steering doesn't load up with too much weight off-center, and doesn't feel antsy with an overly quick ratio, either. With struts in front and a multi-link rear end, the front-drive Regal is responsive enough, its handling tempered with a fair amount of lean.

The Regal also can be fitted with a new all-wheel-drive system, one with electronically controlled limited-slip differential at the rear wheels and with a differently designed rear suspension to accommodate the drivetrain. It can split up to 90 percent of its available torque to the rear wheels, or shift torque between rear wheels with an electronic limited-slip differential. The result: better response to on-power cornering, and maybe more important, a few thousands more interested buyers who put AWD in the "must-have" bin.

At the midpoint in wheelbase and overall length of compact and full-size--think Ford Focus and Fusion--the Regal doesn't come up shy in front-seat space. Base models have more mildly shaped seats than the GS' buckets--they have much better bolstering--but they're all trimmed in leather. We'd ask for more support on the base Regal's bottom cushions, but head and leg room aren't constrained, unless you slide the seat forward and opt into the sunroof.

Cargo capacity isn't the Regal's strongest suit, either. With just 14.3 cubic feet of trunk room, it's about 3 or 4 cubic feet smaller than other sedans, and a piece of luggage less than the enormous 20-cubic-foot trunk in the Ford Taurus.

The Regal doesn’t have much of a problem with visibility, and uplevel Regals do have rear parking sensors, with an option for front sensors. Still, some of its new safety options may appeal: adaptive cruise control, blind-spot monitors, a lane-departure warning system, and a forward-collision warning system are all now available in the Regal.

In IIHS testing, the Regal has achieved top 'good' scores in every category; and when properly optioned, it earns the 'Superior' rating for front crash prevention.

The National Highway Traffic Safety Administration (NHTSA) awards the Regal a rating of five stars overall. It's given four stars for front-impact protection and rollover resistance, but five stars for side-impact protection.

The base version is no longer the eAssist; a turbocharged model takes its place as the least-expensive Regal.

All Regals come with leather-trimmed front seats with a power driver seat and seat heating; a rearview camera; a leather-trimmed steering wheel; automatic climate control; cruise control; power locks, windows, and mirrors; and an AM/FM/CD/XM audio system with a USB port.

The Regal eAssist and Regal Turbo sedans with Premium packages get remote start; rear parking sensors; a heated steering wheel; and a power passenger seat.

The audio system and the Regal's connected mobile phones are controlled by IntelliLink, which has a large 8-inch LCD touchscreen integrated into a much less complex center stack of controls. The touchscreen interface allows users to reconfigure the home screen, to choose up to 60 favorites across its suite of applications, and to store up to a thousand contacts--while integrating smartphone-based streaming audio and accessing navigation with natural-voice commands. IntelliLink also displays redundant information on a 4.2-inch screen tucked between the gauges.

The Regal GS with front-wheel drive has the adjustable suspension as standard equipment and its own 19-inch wheels; 20-inch wheels and summer tires are an option, as is a sunroof. Also on the Regal GS, the center of the gauge cluster swaps out for an 8.0-inch LCD screen with customizable looks for different driving modes (Touring and GS). The Regal GS also offers the lineup's only manual transmission, a no-cost option. 

The eAssist had been the base Regal since the 2012 model year, when Buick dropped its non-turbo, non-hybrid standard engine. Last year, a less-expensive version of the turbo supplanted it as the entry-level Regal. The eAssist combines lithium-ion batteries and motors to boost acceleration when the Regal accelerates--in tandem with a larger-displacement four-cylinder engine--but it's a bit more limited in scope and intent than a true hybrid. The Regal eAssist can't run on electric power alone, for example.

As a result, its EPA gas-mileage ratings of 25/36 mpg, or 29 mpg combined, aren't in the same league as the Ford Fusion Hybrid's 47/47-mpg rating, or the new Honda Accord Hybrid's 47-mpg combined rating. In fact, it's not much more than the non-hybrid Hyundai Sonata and Kia Optima, or the EcoBoost 1.6-liter Ford Fusion--and it falls well behind the 38-mpg highway registered by the Nissan Altima.