2012 Infiniti G Sedan

Success doesn't rest on its laurels. When the 2003 Infiniti G35 sedan hit the streets, it was an immediate hit. The mid-size sedan was slick looking, fun to drive and relatively affordable. Instead of letting the car grow stale, or even get slightly crusty, Nissan's luxury brand redesigned it for the 2007 model year. Now, Infiniti is upping the power and adding a new transmission. With the new engine comes a name change: the G37, and it's quite possibly Infiniti's best sport luxury sedan yet.

Model Lineup
The G37 sedan is offered in four trim levels: G37, G37 Journey, G37S Sport MT and G37x AWD. All are well-equipped. The base G37 comes with leather upholstery, automatic climate control, keyless entry and starting, XM satellite radio, bi-xenon headlights and 17-inch tires on alloy wheels. The G37 Journey adds dual-zone automatic climate control, 6-disc CD changer and automatic headlights. Infiniti offers the G37S Sport MT as its performance version. It is the only one with a manual transmission, and it comes with sportier suspension settings, a limited-slip differential and 18-inch performance tires. The G37x model has Infiniti's Intelligent all-wheel-drive system, plus heated front seats and heated exterior mirrors.

A Sport package for Journey and Sport MT trims comes with sport suspension, 18-inch wheels, a limited-slip differential, larger brakes, sport seats, a more aggressive front fascia and, for the Journey, steering-wheel shift paddles. Also offered is Infiniti's Four-Wheel Active Steer system, which is teamed with stiffer shocks and variable steering ratios.

Standard safety equipment on all versions includes dual front airbags, front side airbags, side-curtain airbags, a tire-pressure monitor, active front head restraints, anti-lock brakes with brake assist and electronic brake-force distribution, traction control and electronic stability control.

Under the Hood
The 2009 Infiniti G37 sedan gets Infiniti's 3.7-liter V6, which first appeared in the G37 coupe for the 2008 model year. It produces 328 horsepower, up from 306 horses in the 2008 G35 sedan. The new engine has Infiniti's Variable Valve Event and Lift (VVEL) system, which is a form of variable valve timing for the intake stroke. The engine is offered with a 6-speed manual transmission or a new 7-speed automatic with manual shift capability and Adaptive Shift Control that learns the driver's driving style and adjusts accordingly. The new transmission and VVEL system raise Environmental Protection Agency fuel-economy ratings by one mpg in the city and two mpg on the highway, to 18/26 mpg (city/hwy). With the manual transmission, EPA fuel economy ratings are 17/25 (city/hwy).

The G37 comes standard with rear-wheel drive, and the G37x has Infiniti's Intelligent all-wheel-drive system, which it calls Advanced Total Traction Engineering System for All Electronic Torque Split (ATTESA E-TS). This system is rear-drive biased. Under normal conditions, it sends 100 percent of the power to the rear wheels. When slip is detected, it can actively distribute up to 50 percent of the torque to the front wheels thanks to a locking center differential. AWD comes only with the automatic transmission. EPA fuel economy estimates are 18/25.

Inner Space
Take a seat in the G37 and you notice that it has a premium feel. The controls are within easy reach and move with precision. At the center of the dash is a 7-inch display with a control panel to operate the navigation system and/or information center. The control panel may seem a bit complicated at first, but the radio and climate controls are separate, so the learning curve is short.

Infiniti's optional navigation system comes paired with the company's 9.3-gigabyte MusicBox hard-drive music system. Order the Premium package and you also get an iPod interface that charges your iPod and lets you control it through the radio. For those with other types of MP3 players, the G37 has a standard auxiliary input jack.

Compared with its natural competitor, the BMW 3-Series sedan, the G37 sedan offers more interior space. Front-seat room is about the same, but the rear seat is considerably better. The G37's rear seat will accommodate two passengers fairly easily, but three will be a stretch and someone will have to sit on the hump. Front-seat occupants have plenty of headroom- and legroom. The Sport package's sport seats have extra side bolstering that helps hold occupants in place during aggressive cornering. Some may find the seats a bit firm.

Complaints about the G37 are minor and revolve around carrying capacity. Small-items storage consists of a shallow center console, two cupholders behind the shifter, the glove box and front door pockets with integrated bottle holders. Another bin or tray would be nice. The trunk has a decent 13.5 cubic feet of volume, but the G37 sedan has a center pass-through instead of a split folding rear seat. That means you can carry skis, but a snowboard and long boxes may not fit.

On the Road
The G37 sedan provides a sportier driving experience than any competitor other than the BMW 3-Series. Most noticeable is the steering. Grip the tactile steering wheel and you feel very connected to the road. The steering is also very direct, which makes the car react quickly to input.

Even the standard suspension is sporty. All G37s exhibit little body lean in corners and feel agile in quick changes of direction. Ultimate grip isn't as tenacious as in a BMW 3-Series, but the G37 will thrill anyone who looks for driving excitement. Plus, the G37 offers two more levels of sportiness. The available Sport package has firmer suspension settings and 18-inch wheels that give it sharper moves. The optional Four-Wheel Active Steer system is firmer yet, and it makes the G37 react even quicker.

I would recommend the Sport package, but would advise customers to try the Active Steer system on a bumpy road before they buy. The base suspension setup is fairly forgiving, and the Sport suspension is firmer but not punishing. Active Steer comes with even firmer suspension settings that can make it pound over bumps and jiggle on broken surfaces. Rust Belt buyers will want to avoid it.

The 3.5-liter V6 in the 2008 G35 was one of the best engines on the market, and the 2009 model's 3.7-liter V6 is even better. Infiniti says it propels the G37 from zero to 60 mph in one- or two-tenths of a second faster than the 2008 model, which could reach 60 in as little as 5.3 seconds. That's V8 power in a V6 package. The new 7-speed automatic transmission is smooth and responsive, and it combines with the powerful engine to provide immediate and confident passing response. The Sport package's steering-wheel paddles add a fun factor during aggressive maneuvers, and the available 6-speed manual shifts easily, though it's a bit notchy.

Right for You?
The G37 is aimed at buyers more interested in sporty performance than a cosseting ride. It is a fine alternative to luxury sedans from BMW and Mercedes-Benz. Its strengths include good looks, willing power, a premium interior with useful space and available all-wheel drive. Add in prices lower than those of the more established brands, and the G37 should be on the shopping list of anyone looking for a luxury sedan.

Kirk Bell has served as the associate publisher for Consumer Guide Automotive and editor of Scale Auto Enthusiast magazine. A Midwestnative, Bell brings 18 years of automotive journalism experience to MSN, and currently contributes to JDPower.com and Kelley BlueBook's kbb.com.