28.5.2009 Lexus RX 450h review

With a hybrid development featuring in almost every model of its line-up, Lexus, the luxury arm of Toyota, enables even posh car buyers to go some way to satisfying thier environmental conscience, which Iain Robertson suggests is just dandy!

By building the RX 450h in the World's first dedicated hybrid-only plant, Toyota is living up to its promise to produce some of the cleanest and greenest vehicles available. Developing 10% more power but consuming fuel at a 23% reduced rate compared with the outgoing 400h version of the RX crossover vehicle, is a measure of the commitment. The Power Control unit (which incorporates an ECU, DC/DC boost controller and an AC/DC converter) is miniaturised and no less than 8kg lighter than before. The same applies to the battery pack located beneath the rear seats, which also takes up less space than before.

As the Lexus brand has certain up-market, premium aspirations to attend to, its engineers have focussed on high-speed cruising comfort. Stiffening the body shell has helped with the car’s ride quality, although I found that the optional air suspension is better for the passengers, rather than the driver. A revised suspension hardware set-up places double wishbones on the rear axle and frees up some extra boot space as a result. If you opt for the standard steel sprung suspension, an active stability system aids control and creates a surprisingly sporty ride and handling compromise.

Now lowered to improve weight distribution and create a lower centre of gravity, the 3.5-litre V6 engine is mounted transversely. The engine has been altered quite dramatically over its forebear, and with apologies for being too 'techie', the new unit uses an Atkinson Cycle, as opposed to the more normal Otto Cycle engine fitted to 99% of all petrol cars. While being more economical, it develops a substantial 295bhp, which is enough to whisk the car from 0-60mph in 7.5 seconds, with a top speed in the order of 125mph – that said, it’s worth remembering that the ‘h’ in the model designation is meant to highlight the car’s hybrid, not sportscar-like performance.

Of course, hybrids (and SUVs) have come in for a lot of criticism recently, and there remains an urban myth that the increased cost of manufacturing a hybrid, notably to the environment, undoes any benefit from improved fuel economy and reduced emissions – a myth that we at WhatGreenCar easily dispel through comparing our ratings for hybrid and conventional models. Given that hybrids generally reduce fuel use (and CO2) by around 20-25%, the 450h's fuel economy figure (Official Combined) comes in at a remarkable 44.8mpg, with CO2 emissions of 148g/km – remarkable for an SUV that is. On running costs alone, the Lexus is said to be £2,544 cheaper to run than the X5 3.0D and £3,870 cheaper to run than the ML320CDi for the first 6,000 miles, according to the blurb, although what happens to the costs after 6,000 miles is not declared.

As with the current model, the interior styling of the updated RX remains a strong feature. Within the frame is an exceedingly comfortable and cosseting interior, the driver being fronted by a broad sweeping dashboard and a transmission selector mounted high on the centre console, which also forms a bridge with some fairly useless storage beneath it. Swathes of fine quality hide cover most wear surfaces and the dash is produced from soft-touch plastics, also of very high quality.

A mouse controller has also been added to the new Lexus. Fitting the average size of hand comfortably, much like the i-Drive system on a BMW, it is located behind the gearlever on the centre stack and allows access to all major functions of the car. Among those items are both adaptive cruise control, with radar function, and a Mark Levinson ICE package that includes speakers that all hi-fi fans will love, so good is the reproduction quality. Satnav and various readings related to the hybrid operation are also in included.

Unsurprisingly perhaps, the list price is not exactly in the bargain basement, even for a brand that does not hold quite the cachet of a BMW or Merc. The range starts at £41,600, rising to £55,503. Mind you, although it is hardly a mainstream offering, with 200,000 Lexus hybrids already sold, this new model is likely to add to the model's success – Lexus UK expects to sell arouind 3,000 in the first year. Even though more costly than a comparable BMW or Merc, a significantly higher standard equipment level means that those cars would cost upwards of 10% more to equip similarly.

Personally, I can understand why a company executive would love one given its high-spec and relatively good fuel economy (for its class), helped in no small way by the fact that the 450h will run as an electric vehicle for a greater distance than before. With its low(ish) CO2 emissions (again for its class), execs will certainly be tempted by the new model’s BIK rate of just 14%. While I think it is subjectively ugly, there are plenty of people that love the RX450h, and the new offer is markedly better than the original.

FIRST-DRIVE FACTS:
Model tested: Lexus RX450h
Body-styles: 5-door crossover hatchback
Engines: 3.5 (P/EH V6)
Trim grades: Exec, SR, SE, SE-L
Prices: from £41,600 to £55,503
In the showroom: July 2009
Review star rating: 5 STARS
Warranty: Three years, 60,000 miles

Iain Robertson © WhatGreenCar.com 2009