Infiniti FX Performance
The 2008 Infiniti FX has surprisingly sports car-like performance, in part due to its light weight. Despite being an SUV, the FX is not intended for off-road performance, but drives well in the snow.
According to Edmunds, "You need just a few minutes behind the wheel of the FX35 to realize that Nissan's claim of near-sports-car handling is virtually true."
Acceleration and Power
FX35 models have a 3.5-liter 275-horsepower V6 engine, while the FX45 has a 4.5-liter 320-horsepower V8. The V6 engine, also used in the Nissan 350Z, gives the FX35 its sporty performance. Car and Driver reports, "The FX35's pace is surprisingly close to that of the FX45, which has a much more powerful 315-hp V-8. We measured the sprint to 60 in 7.1 seconds and the quarter-mile in 15.5 seconds at 91 mph (6.3 and 15.0 in the FX45). Top speed was an ungoverned 137 mph, enough to see off most expensive German sedans with their 130-mph governors."Cars.com adds, "Acceleration is so eager that one begins to question the need for a V-8." But U.S. News reviewer Rick Newman notes "there was noticeable lag when accelerating and a bit of lurching when shifting into overdrive." The base model FX35 has an Environmental Protection Agency-rated gas mileage of 15 city/22 highway and the AWD version is rated at 15 miles per gallon in the city and 20 miles per gallon on the highway.
If reviewers are pleased with the V6, they are even more complimentary of the powerful V8 engine. New Car Test Drive says that "the step up to the V8 is noticeable, particularly when you stab the gas at, say, 60 mph. The FX45 will rocket to 80 at a much greater rate than the FX35. However, with gas prices rising, one must note that the V8 also chugs fuel at a much greater rate, reducing range between fill-ups by anywhere from 25 to 75 miles, according to the EPA's numbers." And, according to Kelley Blue Book, "[t]he extra cost of the V8 is hard to justify considering you can load the FX35 with every option imaginable for the price of a base FX45." The FX45 is rated by the Environmental Protection Agency for 13 miles per gallon in the city and 17 miles per gallon on the highway.
Both the FX35 and FX45 have five-speed automatic transmissions that can be placed in "manumatic" mode for stick shift-style performance. CNET calls it "smooth-shifting" and the finds it "responsive" with "an easily used manual shift feature."
Handling and Braking
The 2008 Infiniti FX wants to be a sports car among SUVs, and for the most part reviewers agree that it succeeds. All models have engine-speed-sensitive variable-assist power rack-and-pinion steering and an independent suspension (sport-tuned on the FX45). Edmunds says, "The FX35 holds the pavement far better than most SUVs and maintains that grip tenaciously, even through demanding mountain curves and grades. Turning the wheel is a pleasure." Kelley Blue Book similarly feels that "the FXs' impressive handling and brutally quick acceleration make them the ideal performance crossovers."
The ride is comfy, too, especially in the less expensive FX35 model. According to Auto Mall USA, "The FX35 without the Sport package rides more smoothly and more pleasantly [than the FX45]. It's still plenty nimble and quick and fun to drive. But its suspension is slightly more compliant, more comfortable in most situations, and its higher profile tires take some of the crack out of bumps and expansion joints. However, even the FX35's suspension is on the firm side and the ride gets a little bumpy on rough streets at low speeds. Some drivers prefer the ride quality of the FX35 over that of the FX45."
Kelley Blue Book finds the tires and the suspension responsible for both good points and bad points in the FX's ride: "While their grip is not in question, the firm ride of these round rubber giants might be somewhat unsettling. Once under way, the FX's steering is tight and linear, responding instantly to the driver's input while the sophisticated suspension keeps the FX nearly level in all but the most extreme cornering maneuvers. The steering can feel a bit heavy due to the large tires, and tight turning circles are not what the FX does best."
Reviewers make it clear that despite its all-wheel drive option, the 2008 Infiniti FX is not for off-road driving, nor is it intended to be. "In terms of off-road capability," writes the reviewer for New Car Test Drive, "the BMW X5, Mercedes Benz M-Class and Porsche Cayenne are better suited for the rough stuff than the FX. Infiniti designed the FX primarily for on-road performance, with an available all-wheel-drive system intended primarily for improved handling and performance in the snow."
FX35 3.5-Liter V6
The 3.5-liter FX35 comes standard with a 275-horsepower six-cylinder engine and electronically controlled five-speed automatic transmission with manual shift mode.
FX35 AWD 3.5-Liter V6
The 3.5-liter FX35 AWD comes standard with a 275-horsepower six-cylinder engine and electronically controlled five-speed automatic with manual shift mode, plus ATTESA E-TS all-wheel drive. ATTESA E-TS stands for "Advanced Total Traction Engineering System for All - Electronic Torque Split," a technology developed by Nissan that directs torque to the tires with the best traction.
FX45 AWD 4.5-Liter V8
The 4.5-liter FX45 comes standard with a 320-horsepower eight-cylinder engine, electronically controlled super-wide ratio five-speed automatic with manual shift mode, plus ATTESA E-TS all-wheel drive and sport-tuned suspension.