Chrysler slips a new eight-speed automatic into its V6-powered 300 for 2012. We test out this 31 mpg sinister street machine.

Although Chrysler's much-ballyhooed 3.6-liter Pentastar V6 landed in its flagship sedan last year, the big 300 sedan's revitalization was missing one key element: A 21st century transmission.

But Chrysler has answered our requests for 2012 with a new ZF-developed eight-speed unit that out-gears anything else at this price point. To test it out, we hopped behind the wheel of one of the most dressed-up Chryslers you'll find, a 300S - that's S for styling, apparently, as this one has been heavily tweaked.

What is it?

Now in its second generation, the Chrysler 300 has seen a more serious paradigm shift in its V6 variants than you might realize. While the range-topping 300C retains a 5.7-liter HEMI V8, the base 300 scraps its old and genuinely bad 2.7 and 3.5-liter mills in favor of an all-new 3.6-liter V6. This same engine is also found in nearly every Chrysler product larger than a compact, but the 300 and its Dodge Charger kissing cousin are the first to gain access to the new eight-speed.

Extra gears mean normally two things: Better fuel economy and increased performance, and the 300 delivers. Officially, the EPA rates the eight-speeder at 19/31 mpg, while the old five-speed was rated at 18/27. The V6's output remains unchanged, but its power band is more readily accessible.

The eight-speed is now standard on all V6-powered 300s (the base Charger retains the old five-speed), but we figured we'd try out the most outlandish trim level, the new-for-2012 300S (that's capital S). In addition to its interior and exterior styling upgrades, it also brings with it a Beats-branded 522-watt audio system.

Both rear and all-wheel-drive versions of the 300 come with the eight-speed automatic, but our tester sent its power to the two back wheels.

What's it up against?

In addition to its cross-showroom Charger rival, the 300 squares off against a bevy of front and all-wheel-drive competitors.

Think Toyota Avalon, Lincoln MKS and Buick LaCrosse and you're in the right ballpark. But only the Chrysler twins will please enthusiasts with their decidedly handling-oriented chassis.

How does it look?

Last year's redesign didn't really take the 300 in an all-new direction, but it did certainly refine the car's shape. What was jaw-dropping in 2005 has morphed into a rather urban style accentuated by our tester's S package.

The 300's proportions remain boxy, although its more clearly defined greenhouse and vastly improved tail give it a much more modern appearance than the old car.

Big 20-inch alloy wheels and a blacked out front grille set the S apart from more mundane 300s. The S package is available in a variety of colors, but black seems perhaps the most appropriate for its sinister look. Only its excessively accentuated and unadorned slab-sides seemed amiss when swathed in this glossy, non-metallic shade.

And on the inside?

Striking but certainly not elegant, our tester's black and red color scheme was impossible not to notice. Something about the bright red shade chosen for the seats and armrests felt a bit off to us, but we can't fault Chrysler for at least trying to be interesting. Other trims are available.

That admittedly subjective assessment aside, the 300's interior is otherwise a nice place to whittle away the miles. A big four-spoke steering wheel with convenient behind-the-spokes audio controls sits in front of blue-illuminated gauges that err just the right side of tacky. From there, a gigantic touch-screen LCD holds sway in the center of the dashboard, while simple climate controls give way to a toggle lever for the eight-speed transmission.

The Uconnect touch-screen's menus are perhaps the industry's most intuitive; while we'd like to see a few functions (heated seats and steering wheel, in particular) removed from the menus and given physical dashboard buttons, the system otherwise serves as a template of how to do infotainment right. Are you listening, Ford, BMW and Audi?

On the other hand, the goofy nub that controls the eight-speed automatic is a confounding gimmick that serves only to reinvent an item that worked rather well before. Push it forward - but not too far forward - and you'll probably engage reverse. Or you might wind up in park. Neutral? Anything is possible. We unintentionally revved the engine in neutral too many times during the course of our evaluation.

Luckily, the rest of the interior generally impresses. Those bright red seats are supremely comfortable and they're covered in the kind of sumptuous leather Chrysler seemed to ignore until recently. So to the rest of the interior trim; soft-touch plastics cover just about every surface, and we even liked the vaguely carbon fiber-esque appliques on the dashboard, doors and center console.

Rear seat passengers are treated to excellent space and the large trunk features a huge opening, although the Beats subwoofer takes up some space. We wondered for a bit if that subwoofer was actually functional, however, since the Dr. Dre-developed Beats system was nowhere near as aurally stimulating as we were hoping it would be.

But does it go?

While the ZF-developed eight-speed automatic is brand new to the 300 for 2012, its 3.6-liter V6 is a carryover. But that's not a bad thing, since its 292 horsepower and and 260 lb-ft. of torque have never struggled to motivate this big, two ton sedan.

Officially, Chrysler pegs the 300S at 7.2 seconds in the naught-to-60 mph sprint, which seems realistic from our testing. The V6 furnishes good power available from immediate tip in, although it really comes alive over 4,000 rpm. The eight-speed automatic shifted quickly and nearly imperceptibly, although we found it to be a bit on the gruff side during its first handful of cold weather shifts. Once the engine warmed up, it seemed to settle into its groove.

Engaging sport mode resulted in marginally faster shifts and a bit of additional gear holding, which gave the 300S a zippier feel overall.

The smooth V6 was a silent companion aside from a muffled, refined growl that kicked in around 3,000 rpm.

As tempted as we were to drive our test car aggressively, we held off to measure fuel economy. On the highway, we couldn't quite hit the EPA's 31 mpg figure, but our 30 mpg finding was still impressive. Overall, mixed driving netted 24 mpg, which was 1 mpg above the EPA's estimate.

Despite the loss of two cylinders, the V6-powered 300 shares most of its V8 brother's firm but compliant suspension. Derived from an older Mercedes-Benz E-Class, the 300's architecture has been thoroughly updated. Only an occasionally flinty feel over pockmarked concrete distracted from an otherwise well-controlled, coddling ride. Blame might go to the 300S' 20-inch wheels and their mediocre Firestone tires.

One of the biggest improvements the 300 saw back in 2011 was its vastly revised hydraulic power steering, which offers limited feel but substantially better control. Still a little slow to return to center, the tiller is generally quick to respond to inputs.

For once, the 300 can hold its own on both the highway and a winding canyon road, regardless of the engine under its long hood.

Why you would buy it:

The Chrysler 300 now offers midsize car fuel economy in a no-compromise full-size package.

Why you wouldn't:

You're stuck in the 20th century, when V6s were just not good enough.

Leftlane's bottom line

We love the growl and power offered by Chrysler's 5.7-liter HEMI V8, but this new ZF-developed eight-speed automatic mates so well to the 300's base V6 that most buyers will be more than satisfied.

The 300 makes other full-size sedans seem like weak, uninspiring efforts, especially those that promise fuel economy but only deliver middling performance. In fact, even the most hardened enthusiast and power lover might want to pause before automatically making the jump to a V8.

2012 Chrysler 300S base price, $33,170. As tested, $40,460.

SafetyTec Package, $2,420; Luxury Group, $3,250; Uconnect Touch, $795Destination, $825.

Words and photos by Andrew Ganz.