Nissan has created one of the best-selling mid-sized crossover SUVs ever with the Infiniti FX45. Infiniti is luxury car brand from parent company Nissan that started producing the FX models in 2003. The FX models replaced the QX4 as Infiniti's luxury SUV. The FXs have been made to be larger than the QX4s, but still remain classified as mid-sized. Some of the most notorious competitors for the Infiniti FX models are the Volvo XC90, the Volkswagen Touareg and the Porsche Cayenne.

With a displacement rating of 4494 cc, the FX45 features micro-finished camshafts and crankshafts; aluminum engine blocks and heads; molybdenum-coated pistons and titanium exhaust and intake valves. Further is has been engineered with modular cylinder heads and a single stage cam drive shaft that runs as silently as the "bionic cheetah" that the car was designed after. Infiniti engineers saw the FX45 as a low-sitting, sleek and aggressive crossover that they refer to as "cool fusion".

The Infiniti FX45 is so named because it utilizes a 4.5L V8 engine. Its platform is the same as the Nissan 350Z, a rear wheel drive vehicle that is about the same size as the Nissan Murano. Of course, Nissan and Infiniti are both Japanese-based automakers, however the FX45 is not for sale in Japan.

As of 2009, the FX45 joins the FX35 and the new FX50 for a second generation. The elegant body of the FX models intentionally remind one of a vintage sports car. They are also very intentionally designed to provide the upmost in comfort and performance. Case in point, the "Continuously Variable Valve Timing Control System" maximally enhances the opening of the intake valves. The FX series is also the first ever to have offered the lane departure alert system. This system uses a camera to observe the center and side lines on a given road and alerts the driver and passengers of unintentional weaving with a buzzing alarm.

Further, the FX45 (and its counterparts) now feature standard heated front leather seats, a 10-way adjustable driver's seat and 8-way adjustable passenger seating. The FX45 comes stock with 20-inch alloy wheels and a completely independent suspension system that grants smooth riding and superior handling.

The largest changes to the FX series came in 2006 when they received facelifts that were quite dramatic. An array of new stock features and available options were also incorporated. The facelift itself incorporated revised wheel designs, new grilles, restyled bumpers and more color schemes. There was also a new color screen added to the center console. The 300W Bose stereo system was made standard instead of optional as was the rear view monitor and the Advanced Airbag System (AABS) .

On March 4, 2008, the new Infiniti FX series was introduced at the Geneva Motor Show. The FX35 and the FX50 will be offered for public consumption with automatic transmissions and the FX45 will remain available only as a manual tranny model for those who just love to do their own shifting. The FX45 demonstrates appreciable speed and power going from 0 to 60 mph in just under 6.5 seconds and running the 1/4 mile in 14.8 seconds. Infiniti is naturally excited about the new generation of the FX series and expect sales to remain solid as the 2nd generation arrives.