The G37 Sedan is one of the most responsive, communicative, and fun-to-drive sport sedans in its class. Its 3.7-liter V-6 makes more muscle—328 horsepower and 269 lb-ft of torque—than some rival V-8s and provides enough thrust to satisfy most rabid performance enthusiasts, though it's a little more raucous than the former 3.5-liter and not nearly as smooth as BMW's excellent turbocharged six in the 335i.
Reviewers love the performance from the engine. Edmunds calls the acceleration "fierce," and ConsumerGuide reports that the engine "satisfies at any speed" and makes "passing maneuvers...a breeze." Motor Trend reviewers clock times from 0-60 at just 5.0 seconds, "with the quarter-mile obliterated in just 13.5 sec at 105.3 mph."
The seven-speed automatic transmission in the 2010 Infiniti G37 Sedan pulls off snappy and smooth shifts when accelerating hard, but it seems more at home when driving aggressively; shifts become lumpy and indecisive when light on the throttle. Solid-magnesium steering-wheel paddle shifters (included on G37 Journey and G37x AWD models) command a quick downshift, though, including a throttle blip.
Reviews of both transmissions are mixed, but the automatic seems to draw more than its fair share of criticism. Edmunds cautions that "upshifts are never luxury-sedan smooth, even in Drive," and once you "switch to Driver Sport or manual, forget about it—you've got yourself a veritable Lurch-o-Matic." Car and Driver agrees, noting that "upshifts in manual mode could be smoother and more quickly effected." On the positive side, ConsumerGuide calls the auto "alert and responsive," and while it "seems busy in some situations," they find it "generally smooth and prompt" overall.
Those who like a manual transmission will find the six-speed very satisfying. Car and Driver also calls the manual transmission "better behaved" than on previous versions, with "throws [that] remain short but high-effort, the latter a trait shared with the clutch."
Fuel economy is respectable in the 2010 Infiniti G37 Sedan; with the automatic transmission, it now rates 18 mpg city, 26 highway, though TheCarConnection.com fails to meet those estimates. With the manual gearbox, the G37 is rated slightly lower, at 17 mpg city and 25 highway, while the AWD version manages 18/25 mpg.
Underneath there's a firm, sport-tuned four-wheel independent suspension, and power steering adjusts effort according to vehicle speed. The G37 Sedan is quite possibly the best-handling sport sedan, price no object, with great steering feel and near-perfect dynamics, for those who can take advantage of them on the track.
"Steering feel is precise and direct," reports ConsumerGuide, adding that the "available Four-Wheel Active-Steer System provides particularly sharp moves." Edmunds also praises the handling and says that the steering wheel is "alive with information." Motor Trend lists some of the G37's traits as "well-balanced, easy to induce oversteer, taut ride," and calls it "a step quicker" than its predecessor. ConsumerGuide also finds that "braking is strong and secure" on the Infiniti G37.
Kelley Blue Book declares that the Infiniti G37 Sedan is a marvel of suspension engineering, noting that the "finely-tuned suspension delivers [an] impressively balanced ride and handling," making for a car that, when "driven normally...coddles, comforts, and entertains."