Aug 16 2009
Lexus has introduced the next generation of its trend-setting hybrid RX 450h luxury utility vehicle for 2010. Lexus inaugurated the luxury crossover category with the original RX 300 model in 1998 and introduced the first-ever luxury hybrid in 2005. More than one million Lexus RX models have been sold worldwide, making it the most successful luxury utility vehicle. The all-new RX450h hybrid once again raises the bar for design, engineering and luxury innovation in the segment.
The 2010 RX 450h introduces an updated version of Lexus Hybrid Drive, featuring a 3.5-liter V6 Atkinson-cycle engine, lighter electric motors, a smaller and lighter power-control unit and other fuel-saving innovations. It offers up performance similar to V8s with better combined fuel economy than the average four-cylinder mid-size sedan. With EPA-estimated 32 mpg city and 28 mpg highway (30 mpg combined) ratings for the RWD –30 mpg city, 28 mpg highway, 29 mpg combined for the AWD – it earns 16-20 percent better fuel economy than its acclaimed predecessor. All this while producing 295 total system horsepower, which is 27 more than the previous generation RX 400h.
As a full hybrid, the RX 450h can operate in electric-only or gas-engine-only modes as well as a mode that combines the power of both. Extended electric-mode operation during low-speed or stop-and-go driving conditions helps reduce fuel consumption. Under certain circumstances, a new available driver-selectable EV mode can allow the vehicle to be driven short distances using only the electric motors. The RX 450h achieves Super Ultra Low Emission Vehicle (SULEV) certification in California (Tier 2-Bin 3 in other states), producing nearly 70 percent fewer smog-forming emissions than the average new car.
With the Atkinson cycle, the gasoline engine’s intake valves are closed late to delay beginning of compression, resulting in a higher expansion ratio. That reduces intake and exhaust energy losses for more efficient combustion and improved fuel economy. The gas engine alone produces 245 horsepower at 6,000 rpm, up from 208 in the previous RX 400h; torque is 234 lb.-ft. at 4,800 rpm as compared to 212 at 4,400 rpm from the previous RX 400h’s 3.3-liter V6. The Atkinson cycle also reduces exhaust temperature.