Road Test
The idea of creating an SUV that thinks it's a sports car has always struck us as somewhat daft. After all, if you want a vehicle that is quick and responsive, why start with one that is heavy, carries its weight high, and punches a large, ragged hole through the air as it travels down the road?
The BMW X5, however, proved there is a market for SUVs that put more emphasis on paved-road performance than on off-road sloggability. We've even found ourselves appreciating the X5's combination of space, visibility, and responsiveness.
Now Infiniti is taking this concept to the next level with its all-new FX45. Replacing the conventional QX4 in Infiniti's lineup, the FX45 is dedicated to the proposition that an SUV can be successfully crossbred with a sports car.
Based on Nissan's FM chassis, which forms the basis for the 350Z and the Infiniti G35, the FX45 is blessed with the sophisticated aluminum independent rear suspension from those cars, a new strut front suspension, a rigid structure, and a comparatively light 4497-pound curb weight. (A BMW X5 V-8 can weigh between 4800 and 5100 pounds.)
Powered by a 315-hp version of the 4.5-liter Q45 V-8, coupled to a five-speed automatic transmission with obedient manumatic override, the FX45 rushes to 60 mph in 6.3 seconds and through the quarter-mile in 15 seconds flat at 93 mph. That makes the FX45 the quickest production SUV we've tested since the long-dead GMC Typhoon. The FX45 is even able to show its fat tailpipes to the BMW X5 4.6is and Mercedes ML55 AMG (6.5 seconds each).
Handling and braking are similarly capable. Thanks to firm springs, taut shocks, and thick anti-roll bars, the FX45 responds with singular precision on a twisty road. Body roll is minimal, steering feel is excellent, and the overall handling balance is remarkably neutral when you really start pushing its limits.
Part of the credit for the FX45's balanced and natural feel goes to its ATTESA E-TS four-wheel-drive system. You don't need to know what the alphabet soup stands for, but what it does is use a computer-controlled hydraulic clutch to shift the power seamlessly among an infinite range of choices, from a 50/50 front-to-rear split to all of it going to the rear axle. We haven't tried the system in the snow yet, but it sure delivers traction on dry pavement.
With this system coupled to 265/50 Goodyear Eagle RS-A gumballs mounted on standard 20-inch wheels, it's not surprising that the FX45 generates serious cornering grip. We measured 0.87 g on the skidpad. And when you stomp on the ABS-equipped four-wheel disc brakes, this massive helping of rubber brings the FX to a halt from 70 mph in just 160 feet. Both of these figures are the best we've ever measured for a sport-utility vehicle.
Infiniti designers have given the FX45 an appearance that matches this sporty demeanor. Casting approximately the same-size shadow on the pavement as an Acura MDX, the Infiniti's roofline is nearly four inches lower. This squatter profile, combined with its rounded contours, creates an unmistakable aura of muscularity, more in the vein of a Dodge Viper than the broad-shouldered pickup toughness of most SUVs. Wearing the Liquid Copper paint of our test example, the FX45 simply oozes road presence.
Inside, the FX45 looks and feels rich, with genuine aluminum trim used to highlight the prominently grained leather upholstery that does a credible job of mimicking the hides used by the likes of Ferrari. The console lid, the arm rests, and the door panels touched by your elbows all feel extravagantly cushy, and the overall control layout is excellent.
