Note: this first take is based on CNET's drive of an American-spec Lexus RX450h at a media event. Australian specifications and pricing have yet to be confirmed; check back soon for a full review.
The new generation hybrid RX is called the RX450h, as Lexus has bumped up the V6 petrol engine's capacity up from 3.3 litres to 3.5. Lexus says the hybrid system can now deliver 220kW of power and 181Nm of torque — up 20kW and 28Nm respectively — and the extra power is evident whenever we mashed the accelerator. With a host of technologies to improve fuel efficiency — such as Atkinson cycle engine valve timing and an exhaust recirculation system that keeps the petrol engine warm, making it possible to shut it down more frequently — which in US testing has improved slightly to 8.7L/100km.
Thanks to newer battery technology, Lexus was able to make the RX450h's nickel-metal hydride battery pack that sits under the rear seat, a little smaller. When combined with the new double-wishbone rear suspensions it gives the new hybrid RX an extra 22 litres of luggage space.
We piloted a sport-trimmed model over northern California's twisty mountain roads, which should closely approximate Australian models. Steering is vastly improved over the RX400h's, with much more resistance and feedback. Although the tyres sang during hard cornering, the sports-tuned suspension kept the car reasonably flat. Of course, the trade-off is that the ride doesn't feel as soft as the RX400h's.
For all but the hardiest car buff, the exterior and mechanical changes are a case of steady as she goes evolution. On the inside though, the redesign is far more dramatic. One of the most notable features is the voice-command system, which can parse sentences for keywords to enact commands. For example, you can say "I'm cold" and the car will turn up the temperature. Likewise, with the Bluetooth phone system, you can say "Can you buzz George in his office?" and if you have someone named George in your phone book with an office number, the system will dial that number. Unfortunately, these type of voice commands don't extend to your music collection.
Lexus has also added a square joystick on the console to control an on-screen cursor. Although it's the first time we've seen an actual cursor on the screen of a production car, it should be a familiar sight for anyone who's ever touched a computer — hey, how are you even reading this otherwise?
You can change the settings for the cursor, such as cursor shape and greater haptic feedback — in the form of vibrations — when you mouse over a menu item. Alas the joystick doesn't feel very solid, nor does it snap back into its centre position when you move it around, which gives it a cheap feeling. Another oddity is that whilst there are a limited number of icons on any screen, you can still move the cursor all over the place — in a car it seems like it would be wiser to limit cursor movement to clickable items.
The audio system has been upgraded with USB drive and iPod connectivity — at least in models bound for the United States. Another key improvement is the navigation system, which is now hard drive-based. Oddly though, you can't rip music to that hard drive, as you can in most other cars. There's also the option of a rear-seat DVD system that puts LCD screens on the back of the front seats' headrests. A Mark Levinson sound system with 15 speakers was fitted to our assigned vehicle and on a wide variety of music, it produced well-controlled bass; although we could hear the bass thump, it wasn't prone to speaker rattle. The highs were a little shrill, but they were mostly excellently reproduced. We could hear fairly clear notes through the frequencies, but we didn't get a really hard snap from percussion, as we've heard on other high-end systems.
Possibly in an admission that the Chevy Volt and electric cars have stolen the limelight lately, there's an EV Mode button on the transmission, which tries to keep the car running solely on electric power. This seems to be a bit of a gimmick because, according to Lexus, it can do this at speeds up to 16km/h for approximately two minutes. Also included is a sport mode and manual "gear" selection, which holds the transmission at virtual shift points that are really only helpful for engine braking.
We came away from the preview drive deeply impressed with the new RX450h; not only the big improvements wrought on the inside, but also the subtle refinements under the skin. The RX450h won't go on sale in Australia until the middle of 2009 — the petrol-only RX350 is due sometime in the first quarter — and, frankly, we can't wait to put one through its paces on local soil.