First Drive Review: 2010 Lexus RX 350 and RX 450h
This 2010 review is representative of model years 2010 to 2015.
By Tom Wilson of Road & Track
St. Helena, California — Massive sedans may be the traditional model for luxury auto-makers, but for Lexus such iconic duty is handled by the RX crossover series. Sold in more than 70 countries and easily Lexus' best-selling model, the RX is Lexus' most important vehicle, and certain to appear frequently in the freshen-up rotation.
Such is the case with the 2010 versions of the RX 350 and its RX 450h (previously the RX 400h) hybrid counterpart. Athletic as well as luxurious, these 5-passenger crossovers are much improved, bristling with everything from minor tweaks to bold advances. The all-new design is a good example; every inch benefits from a tauter image, but retains the vital Lexus RX profile and proportion for immediate identification. The look is more masculine thanks to a broader shoulder line, but is also accentuated by refined details such as new brightwork around the side glass.
Inside, the redesigned RX impresses with its intelligent use of space, cleanly elegant design and sharp controls. Passenger room is generous, with seat and telescoping steering column travels accommodating the largest of drivers. Every expected amenity is provided and then some, plus two notably well-executed new options. When the navigation system is ordered — now with a larger 8-in. screen — a Remote Touch controller is provided on the center console. Think of a tilting, rocking, but not rolling computer mouse; it's handy and intuitive — two things sadly lacking in other makers' console controllers — and keeps finger smudges off the screen. The second is a useful head-up display with crisp white numerals.
Audiophiles and ordnance film fans will thrill to the optional Mark Levinson 15-speaker sound system with its exceptionally clean bass. The nav system's understanding voice command system listens and comprehends far better than your children.
Technically, however, the RX 350, and especially the RX 450h, truly excel under the hood and in the wheel wells. A 3.5-liter V-6 is used in both models, with front-wheel drive standard. Detail improvements such as slimmer valve stems, a variable runner-length intake manifold and less restrictive exhaust manifolds combine with the existing variable cam timing for an extra five horsepower and a broader torque curve.
The sole transmission is a new 6-speed automatic with manual capability. An intelligent self-shifter, it automatically skips gears, aggressively locks the torque converter or remains in gear as it senses the driver's inputs.
All-wheel drive is optional. It dispenses with last year's viscous drive in favor of a 35-lb.-lighter multidisc dry clutch system to provide up to 50 percent of torque to the rear tires. Designed for inclement weather, the awd is full-time and without low-range gearing.
For pure gearhead wonderment, however, the 450h hybrid has the electro-mechanical chops. Here the V-6 is converted to Atkinson cycle and fitted with an electric water pump, air conditioning and electric-assist power steering to preserve those functions while in pure electric mode. The 288-volt battery pack and controller are downsized but more powerful, enough so that the controller now requires water cooling. The RX 450h's awd option replaces the gasoline version's driveshaft and rear differential with a second traction motor, which reduces weight and allows smooth power shuttling.
While the 4600- to 4800-lb. RX 450h functions mainly as a gasoline vehicle with electric assist, it does return V-8-like power with estimated 28 mpg city/27 mpg highway ratings — the 300-lb.-lighter RX 350 posts 18 and 25 mpg, respectively, by Lexus' calculations. The RX 450h's combined gasoline and electric power is up by 27 bhp, to 295 bhp total, yet its fuel economy can be up to 12 percent greater.
With a distant exhaust snarl to liven the luxury experience, both RXs gobble twisty roads with sedan-like confidence, never mind the scenery-enhancing tall ride height. A supple ride and increased rear storage space are courtesy of a new double-wishbone rear suspension, while reassurance is found in the 10 standard airbags.
Pricing is not expected to rise meaningfully from its high-$30,000 starting point or mid-$40,000 average. The RX 350 goes on sale in the spring; the RX 450h follows by summer of 2009.