You wouldn't mistake this RX for a fully-fledged mud-plugging SUV, but it does have a classic Crossover look, with pronounced wheelarches that flow seamlessly into both bumpers and doors. Distinctive side window mouldings adopt the arrowhead shape that hallmarks the Japanese maker's L-finesse styling approach and the kink in the bottom of the rear doors that draws your eye to the hybrid badge is a nice styling touch. As with previous RX models, the bodywork is class-leadingly slippery.
Brand followers will recognise this 2012 to 2015-era version by its smart front end incorporating the spindle-shaped arrangement for the upper and lower front grilles that's a central element in current Lexus design. At the wheel, owners familiar with the original post-2009 RX450h model will find fewer changes to catch the eye, with a dashboard divided, as before, into upper and lower zones. Higher up, the emphasis is on an eight-inch colour LCD screen, one of functions of which is a fascinating 'Energy' display showing at any given time what's being powered by or driven by what. You can access this 'Energy' section - and indeed all the other infotainment functions of the system - by using the 'Remote Touch' mouse-style control between the seats, available on all but the entry-level variant and simplified in this revised model for easier use.
Through the lovely leather-stitched wheel, you glimpse instruments that have a beautifully choreographed lighting sequence when you enter and exit the car, the lefthand dial, as usual with Lexus hybrids, being a hybrid indicator rather than a rev counter, encouraging the driver to keep the needle in the blue 'Charge' and 'Eco' segments rather than the white 'Power' section above. Otherwise, things are much as you'd expect from any Lexus. We love the little touches, like the way the dual-speed electric windows automatically slow at the beginning and the end of their opening and closing sequence, so as to reduce cabin noise and vibration when you're on the move. Build quality is beyond reproach, though the use of Toyota switchgear (for those electric windows for example) does lower the tone slightly.
As usual in the rear, two passengers will be comfortable but three will need to be on friendly terms. The bench conceals the three battery packs that power the Hybrid drive system but that doesn't stop it being extremely flexible, sliding backwards and forwards so that either luggage space or legroom can be prioritised and reclining for greater comfort on longer journeys.
Out back, the 496-litre boot isn't especially big by class standards (a BMW X5 will give you 120 litres more) but with all those batteries having to be stowed somewhere, we were expecting a lot worse. Top air suspended models even have a button here for lowering the ride height for easy loading. And if you're not using the rear bench, you can drop it using convenient levers on the luggage bay sides, at which point you'll find that the backrest splits 40:20:40 to perfectly suit the kind of luggage and passenger combo you have in mind. With everything flat, up to 1,760-litres of total space is available.
Lexus has an excellent record for reliability, so when we mention that the RX 450h is its least reliable model, don't get too alarmed. When compared to other SUVs, it's still got a great reliability score. It's just that this class of car tends to be used harder than any other. Look for signs of overenthusiastic off-roading and check all non-engine electricals, such as the touch screen and sunroof/windows. You should have no issues with the hybrid power unit, as these seem to be bulletproof, with some owners having put over half a million miles on them with no adverse effects. As a consequence of this, don't be put off by high miles on a used RX450h. People bought them from new to keep a cap on fuel bills on big journeys, so a very low mileage car should attract caution, as it might well have had a harder life as a city car.
Most owners we surveyed were delighted with the build quality and reliability. We did though, find one who complained that their example suffered with flat battery problems whenever they went away on holiday and left it for more than ten days. We also came across an owner who reported a fuel pump failure. And another complaining of mirror vibrations.
(approx prices based on a 2013 RX 450h SE - ex Vat) Lexus parts aren't particularly cheap and should you take the 4x4 title a little too literally and ground your RX 450h out off road, you could be looking at some high bills. We looked around a little online and came up with some more affordable spare part options though.
For an oil filter, you're looking at paying somewhere between £3 and £8, depending on brand. For an air filter, allow just under £30. A pair of brake pads will cost in the £15 to £25, depending on brand, while fuel filters tend to sell in the £75 to £95 bracket. A water pump is around £130 and a drive belt just over £15. If you have to replace a bumper, it'll be around £160 for the part. Headlight bulbs are around £15 and wiper blades sell in the £8 to £15 bracket, depending on brand.
So what's it like? Well you get in, luxuriate in the beautiful leather seats and enjoy the commanding SUV-style driving position before pressing the starter button to be greeted by.. nothing. The engine's running, true enough. It's just that at this point, it's doing so silently under battery power alone and if you've a gentle right foot, that's all it will continue to use at speeds of up to 30mph before the 3.5-litre V6 petrol engine kicks in, controlled via a six-speed CVT auto gearbox. But before we go any further, time perhaps, for a recap on hybrid technology.
In case you're still unfamiliar with it, essentially this is a method of power that uses a combination of an internal combustion engine and electric motors. The petrol unit in question here is the 246bhp 3.5-litre V6 we've just mentioned and is supplemented by no fewer than two electric motors, here torqier than they were on earlier RX450h models, with one located on each axle. The first 165bhp unit sits on the front axle driving the front wheels. Another smaller motor at the rear contributes a further 67bhp and is thus able, somewhat nominally, to make this Lexus into a four-wheel drive car, though one with a very pronounced frontward power bias.
These motors enable power generated during deceleration or the engine's excess to be stored - in the battery packs that are located under the rear seat. Like all Lexus and Toyota hybrids, the car can be driven by the electric motors only (as it is from start-off for up to 1.2 miles), with just the engine (if you're giving it full throttle) or more usually, with a combination of both. During deceleration and under braking, the engine switches off and both electric motors act as high-output generators, recovering kinetic energy that automatically recharges the batteries for the next time the hybrid system is able to switch back to electric-only mode.
It all sounds very promising, especially if you make the mistake of assuming that the total amount of power this car can transmit to the tarmac is the sum achieved simply by adding the engine's bhp return to the figures generated by the electric motors. According to the Japanese engineers, it's not quite as straightforward that. Still, Lexus does quote a total 295bhp output, enough to take this 2.2-tonne SUV from rest to sixty in 7.8s on the way to 124mph. While this doesn't place the car in the league of the quickest V8 petrol luxury 4x4s, it remains pretty rapid for a car of the RX450h's size and weight.
Refinement is outstanding, even when the engine's going - but then, RXs were always quiet. Especially of course when being driven solely by their electric motors, something that (providing the batteries are fully charged) you can set the car to do for up to 1.2 miles by pressing the provided 'EV' button. It's one of four driving modes on offer, the others being 'Eco' (which tweaks the drive systems for more fuel efficient progress), 'Snow' (for pulling away on slippery surfaces) and 'Sport'.
You can see why Lexus engineers felt they needed to add that last setting. After all, this car has never really been seen as a particularly dynamic choice in this segment but at least selecting 'Sport', via the drive mode switch provided on the steering wheel, makes your progress feel a little less lethargic. It also changes the dash display background colour from blue to red. True, ultimate grip is still unremarkable and the electric power steering still lacks feel but at least response from the helm is a little more immediate and the car responds more instantly to the throttle as the VDIM Vehicle Dynamics Integrated Management set-up controls and distributes power from the complex drive system. 'Sport' mode also programmes the vehicle stability and traction control systems for less intrusive operation.
If you want to go further, there's the option of choosing the more dynamic F Sport variant with its neat lateral damping system which is supposed to increase stability and improve corner turn-in. It does make a difference - but at the expense of the kind of firmer ride that many typical RX customers simply won't want. Ultimately, this Lexus is never really going to be a rival for more dynamically orientated segment competitors like BMW's X5: its priorities lie elsewhere. But what the post-2012 handling and engineering changes can do is make this into a car you'd be a lot more confident in, late for a meeting with a cross-country trip to complete. Especially if you happen to be in the top version with its electronically controlled air suspension.
This is the variant to choose in the very unlikely event that you'll be regularly taking to forest tracks in your RX450h, thanks to the fact that one of the air suspension's four selectable height settings lifts you a bit higher off the ground: in standard form, this car sits only 175mm from the dirt. For the record, there's Hill Start Assist and an approach angle of around 29-degrees to get you up steep slopes and a departure angle of around 25-degrees to help when you come down the other side. But of course, this isn't really any kind of off roader: in fact, most of the time, this car won't even be running in 4WD, with the second electric motor you'll find on the rear axle only pressed into action when lack of traction makes it absolutely necessary. It's all in the name of efficiency of course: as almost everything about this Lexus is.
This isn't the most capable luxury SUV you can buy. It isn't the sportiest to drive. And it's not the most affordable to buy. But despite all of that, it's the only one quite a few well-heeled buyers can justify owning. Once you've bought the thing, after all, its running costs are hugely less than even the most frugal of its diesel competitors.
While other manufacturers dithered over hybrid technology, Toyota's Lexus division got on and developed it. Their first hybrid RX was an impressive achievement and this one added a significantly improved driving experience to existing strengths of comfort, refinement and a high specification.
This post-2012 RX450h has a smarter look and a slightly more dynamic edge than the original 2009 model, but the reasons you'll want to buy it won't really be much different. Quite simply, it's one of the only cars of this kind you can drive with a clear, green conscience. And that's something it's hard to put a price on.