2010 Lexus RX 450h: Review
This second-generation luxury hybrid crossover is the complete package.
- Economy/performance blend unmatched
- Impeccable fit and finish
- Roomy and practical cabin
- Deserves bolder styling
- Tiny climate control buttons
- Gas engine coarser than expected
Introduced in 2004 as a 2005 model, the Lexus RX 400h became the first luxury crossover powered by a hybrid drive system. It was the closest thing at the time to a guilt-free SUV we’d ever seen: luxurious, powerful and more fuel-efficient than its gas-powered sibling, the RX 300.
This year, Lexus is upgrading the RX Series, including its luxe hybrid. Powered by an extensively redesigned version of the constantly evolving Lexus Hybrid Drive system, the all-new 2010 RX 450h benefits from the myriad changes and upgrades to the third-generation RX platform. It combines an impressive array of features and technologies, typical Lexus build quality and a powertrain that offers a segment-leading blend of performance and fuel economy.
The RX 400h is powered by a muscular version of the gas-electric hybrid powertrain introduced in North America by the Toyota Prius in 2001. It was built around a 3.3-liter V6 gasoline engine that could develop 270 horsepower.
The new RX 450h — hybrid model designations are not tied to the gas engine’s displacement— gets a thoroughly revised hybrid powertrain and will be offered in a single trim with either front-wheel or all-wheel drive. Several packages are offered: Premium, Comfort, Luxury, Sports and Navigation, some of them interdependent, with almost 20 stand-alone optional items. Slightly larger than its predecessor, the RX 450h also offers a bit more space for five passengers.
A number of styling elements distinguish the RX 450h from its RX 350 sibling, most notably the design of its grille and front bumper. It also gets a set of exclusive alloy wheels with thinner, split spokes, and blue accents have been added to the headlights, rear lights, hybrid-specific badges and gauge cluster. Finally, the Aurora White Pearl color is another RX 450h exclusive, as well as a black and light gray interior trim package with black accents.
Optional and exclusive on the RX 450h are LED headlamps, complete with headlamp washers that will set it further apart from the RX 350. These will also last longer and draw less power over their useful life.
Under the Hood
Pop the hood and you’ll find an all-new version the high-tech Lexus Hybrid Drive system. It combines a new 3.5-liter V6 engine running on the Atkinson cycle, lighter and more powerful electric motors, and a smaller, lighter and more potent control unit. Under the Atkinson cycle, intake valves close later to delay compression and reduce energy loss. This improves combustion and fuel economy while reducing exhaust temperature. A new system called the Exhaust Gas Recirculation (EGR) system reduces energy loss further, to improve economy by eliminating the fuel enrichment needed to avoid overheating catalytic converters under high loads.
Another new system recovers heat from the exhaust pipe to accelerate engine warm-up and allow the crucial engine-stop function to kick in much earlier, more often and for longer periods, improving fuel economy and reducing emissions appreciably. With its selectable EV mode, the RX 450h can also run short distances on electric power, but only under specific conditions.
The V6 engine by itself delivers 245 horsepower at 6000 rpm, up 37 from the RX 400h’s 3.3-liter V6. Torque is rated at 234 lb-ft at 4800 rpm, up from 212 at 4400 rpm in the previous model. The system’s combined maximum output is 295 horsepower, which is a 27-pony increase over the RX 400h. Yet the RX 450h’s Environmental Protection Agency fuel-efficiency ratings of 28 mpg city and 27 mph highway (26 mpg for the AWD version) are 8 to 12 percent better than its predecessor. The RX 450h is certified as a Super Ultra Low Emission Vehicle (SULEV) in California, which means that it produces almost 70 percent less emissions than other vehicles.
The new hybrid system’s 288-volt nickel-metal hydride (Ni-MH) battery pack, nestled under the rear seat, is smaller and lighter than in the first-generation hybrid RX. The front-wheel-drive RX 450h’s hybrid powertrain uses two electric motor-generators, and the all-wheel-drive RX 450h gets a third one to drive the rear wheels without a transfer case or driveshaft. The power-steering pump, water pump and air-conditioning compressor are all driven by electricity instead of the engine, which reduces parasitic losses, as well.
Designers were also busy reshaping the RX 450h inside. The fruit of their labor is a new cabin that is entirely Lexus-like, with top-quality materials and smooth controls. The instrument panel has stylish swoops, but the actual controls and components are straightforward and pragmatic. The carmaker’s white-on-black gauges with fluorescent needles, for example, are nestled within a large cluster, rather than the old model’s trio of interlaced, cylindrical housings.
Upgrades and several innovative features are discreetly integrated with ease of use and efficiency in mind. The optional navigation system uses a hard-disk drive instead of DVDs to source maps, which are displayed through an 8-inch LCD mounted in the center of the dash. The screen shrinks to a 7-inch display for audio and HVAC settings when the navigation system is not ordered. Either way, graphics and resolution are impressive. And since the screens are placed farther to better remain in the driver’s line of sight and depth of field, reducing visual disruption and distraction, Lexus designed a mouselike controller called Remote Touch and installed it on the center console.
The Remote Touch controller is perhaps the biggest development here. It acts similar to BMW’s iDrive and Audi's MMI systems, but instead of a fixed knob that spins to run various vehicle functions, the Lexus system acts more like a sophisticated computer mouse—moving on multiple planes. It can also be programmed for different levels of tactile feedback, just like a video game controller. With buttons on either side of the unit, controls are accessible by both driver and passenger.
The Remote Touch controller works but requires too much effort, and is, thus, distracting to the driver. Thankfully, the system accepts voice commands as well, and is equipped with some of the best voice-recognition software we’ve ever used. The Multi-information steering-wheel switches also do a good job as redundant controls. The optional heads-up display also offers clear, high-contrast data about your speed and both navigation info and audio system settings.
Predictably, the RX 450h offers a full selection of communications and infotainment features, including optional 12-speaker and 15-speaker audio systems, above the standard 9-speaker unit. Also available are video monitors for blind areas at the side, a back-up camera and automatic high-low beam switching. Passive safety is handled with 10 standard airbags and a rollover sensor in addition to crash-worthy structural elements.
On the Road
The RX 450h has an all-new double-wishbone rear suspension instead of the McPherson strut arrangement on its predecessor. This design typically improves wheel control and handling, but it is also more compact, adding six inches in width between wheelwells in the cargo bay. The front suspension also gets a thicker stabilizer bar and inversely wound springs that prevent angle variations on bumps, and the steering now has speed-variable electric assist. Wider 18-inch alloy wheels and 235/60R18 tires are standard, and 235/55R19 tires optional, mounted on alloy wheels with a hybrid-exclusive design. Their finer spokes bring a touch of elegance to the 450h and arguably make it the best-looking ride in the new RX family.
In spite of its wider tires and longer wheelbase, the RX still turns within a 38.8-foot circle, curb-to-curb. Its brakes also get 2-piston front calipers and larger rotors front and rear. On the road, the crossover is stable and safe, yet rather unexciting to drive, which is in keeping with the nature and intent of hybrid-powered vehicles. In fact, the additional torque of the electric motors and quick-reacting CVT gearbox make the RX 450h better-balanced and more pleasant to drive than its gas-only sibling, the RX 350, on the twisty roads and inclines of the Napa Valley test loop in this first drive.
Right for You?
The RX 450h will appeal to tech-savvy buyers looking for a leading-edge powertrain that delivers an unmatched blend of performance, fuel-efficiency and environmental friendliness. Ironically, the 450h also delivers a better driving experience than the RX 350, with the more balanced performance and better low- and mid-range torque provided by the electric components of its hybrid powertrain, so driving enthusiasts also get a better deal. The RX 450h does cost a bit more than the RX 350. Even so, it is a more complete, balanced and satisfying package overall. And it remains unique in the hybrid crossover segment.
A professional auto journalist for more than 25 years and the founding editor of Sympatico / MSN Autos, Marc Lachapelle is a two-time winner of the Canadian Journalist of the Year award from the Automobile Journalists Association of Canada, an accomplished photographer and licensed racer.