Car reviews - Lexus - RX - 450h Sports Luxury
Luxury, ride comfort, features, quiet engine, low fuel consumption
Room for improvement
Love-hate looks, some acceleration softness, smallish luggage area, over-light steering
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27 Jun 2016
By NEIL DOWLING
Price and equipment
LEXUS markets three RX450h variants using the same three-version designations as employed in other Lexus models.
In the SUV, it starts with the entry-level Luxury at $88,000 plus on-road costs, to the F Sport at $100,000 plus costs, and then the test vehicle, the Sports Luxury at $106,000.
The elephant in the room is the exterior styling of the RX. It follows the bold and unmistakable grille that is styled on a spindle yet looks more like a mechanism for hunting krill.
This abrupt nose is more dramatically styled in the Sports Luxury than the tame Luxury version, designed to show onlookers that the more aggressive face relates to a more expensive sticker price.
Lexus has opened the goodies box with the Sports Luxury badge, starting with 20-inch alloys and rising to perforated leather upholstery with heated front and rear seats, electric tailgate, satellite navigation, wood and leather trim, premium audio, a DVD player and sunroof and fixed glass panel.
The safety list is equally as impressive, eclipsed only by the Mercedes-Benz GLE400, and includes autonomous electronic braking (AEB).
Amongst a comprehensive list, there are also LED headlights with washers and active shadowing to prevent glare for fellow motorists.
The RX450h comes only as an all-wheel drive, cleverly using a V6 petrol engine and two electric motors for drive to the front wheels, and an additional electric motor that can be automatically engaged to power the rear wheels.
Nothing in its price range has this ability, though the value of the feature is subjective to the buyer’s needs.
It is at this point that the extra expense of the hybrid RX should be justified. Buyers unfussed by the hybrid drivetrain can opt for the petrol-only RX350 model that clips the price back on each variant by $8000.
The hybrid claims better fuel economy but this may be offset by the fact this version is more expensive.
Outside of the Lexus family, green-tinged buyers could look at the Range Rover Sport hybrid at $174,700 plus on-road costs the Porsche Cayenne S Hybrid ($143,100 plus costs) or the Volvo XC90 T8 with plug-in hybrid feature at $122,950.
Unlike its rivals that have a spectacular yet daunting options list, the Lexus has few aftermarket choices save for some metallic paint colours at an additional $1500.
The RX is designed as a front-drive wagon and it remains a five-seater for now.
A seven-seater is reportedly in the works but there is yet to be any formal confirmation.
The hybrid has no mechanical link from the engine to the rear wheels, ensuring no need for a prop-shaft floor hump and a resulting flat floor that has the ability to comfortably seat three adults on the back seat.
Doing without the shaft also has the potential to create a spacious boot but the electric motor, drive shafts and particularly the large nickel-metal hydride battery bite deeply into available storage space.
The latest RX is 120mm longer and has a wheelbase stretched by 50mm to boost cabin room. For humans, the RX is accommodating and very comfortable.
The upholstery is not only extremely attractive – neatly perforated leather facings with bold stitching and plump bolstering for both front and rear passengers – but offers a high level of comfort.
Rear passengers can stretch out with excellent leg and headroom and even front occupants don’t feel cramped between the doors and an imposing centre console.
Notably, it has plenty of jiggle room for long trips.
Despite a lower profile and narrowed side glass profiles, the cabin remains airy and bright.
Typical of the SUV genre, the seat height requires little bending or stretching when entering or leaving. In the new generation, the wagon is 20mm lower with a similar reduction in seat height.
Rear occupants have airvents and, in the fold-down armrest, cupholders and a shallow storage space.
The rear seats split and fold and can slide forward to give good flexibility with cargo. A bonus – though one that is becoming increasingly common – is the electric tailgate.
Boot space is good and owners will find little to complain about. However, up against the rivals, the Lexus’ 453 litres (seats up) and 924 litres (seats folded) is comparatively tight against the Jaguar F-Pace at 650-1740 litres Mercedes GLE400 (690-2010) and BMW X5 (650-1870).
The driver has an excellent dashboard with plenty of theatre to keep occupants amused. The cockpit centres on a bright instrument panel though more useful is the head-up display.
A centre console with colour screen, computer mouse-like control and an often overly-sensitive cursor access major communication, ventilation, navigation and vehicle function features.
Initially quite daunting, the user-functions are comprehensive and informative that only take a bit of time to master. Included is a fast connectivity facility.
The audio is a Mark Levinson 15-speaker unit with commendable sound quality.
The cabin also has a fixed glass roof panel and an opening sunroof.
Engine and transmission
Toyota’s perennial 3.5-litre V6 petrol engine is the heart of the RX450h though unlike the unit used in the RX350 – and numerous other Toyota-Lexus models including Kluger, Aurion, ES/GS and Tarago – it uses a different combustion cycle.
This 3.5-litre Atkinson Cycle engine better suits the needs of a hybrid system by being high on efficiency but less potent on power than its conventional sister. The engine difference is internal, centering mainly on the extended timing of the valves.
It has 193kW at 6000 of power – up 10kW on the previous engine – and 335Nm of torque (up 18Nm) at 4600rpm. This compares to the RX350 non-hybrid engine with 221kW at 6300rpm and 370Nm at 4600-4700rpm.
The diminished power and torque doesn’t matter in the end – the two engine-mounted electric motors (123kW) and the on-demand rear-mounted motor (50kW) take the combined power to a healthy 230kW.
If you ask why the combined power isn’t 366kW, it’s because the power of the engine and the motor arrive at different points in the rev range – the motor at low revs, the engine at higher revs – so they never have a chance to properly culminate.
Toyota doesn’t disclose the combined torque figure but it is estimated at 400Nm. Again, the three motors deliver maximum torque at near zero-revs and the engine at 4600rpm so they rarely have a chance to combine.
The upgraded V6 gets more power and torque thanks to a high compression ratio and the new dual injection system of port and direct injection. Each has particular strengths depending on demands on the engine and computers can switch between the two or engage them simultaneously.
The engine also has features designed to reduce noise and vibration and fuel-saving techniques including electric-assisted power steering and an electric-powered air conditioner compressor.
Lexus claims a fuel consumption average of 5.7 litres per 100 kilometres – a substantial drop on its similarly-sized petrol-fuelled rivals. On test the RX450h averaged 6.6 L/100km with city and stop-start routes recording the lowest fuel consumption figures.
The engine does not have a conventional alternator or starter motor, but uses one of the two engine-mounted electric motors. Cleverly, this single motor will start the engine, act as a generator when the regenerative brakes are engaged and will help its twin to produce extra power when needed.
The RX450h – like the other Lexus and Toyota hybrids – uses a continuously variable transmission. But unlike the more common cone-and-belt system, the Toyota-Lexus unit has planetary gears that better suits the need to split drive from the engine and/or the motors.
The advantages of a planetary-gear CVT are its compact dimensions and light weight, the ability for the unit to find the best ratio to suit engine/driver/road demands the seamless and quiet nature of the unit low fuel consumption and low maintenance.
On the road the package gives acceleration that is more linear and relaxed than the impressive power output would otherwise indicate.
It’s not fast, but certainly no slouch and the relaxed nature of the drivetrain delivery can mask the wagon’s speed. Initial acceleration, low-speed driving and any reversing is done predominantly in electric mode.
The driver can switch to electric-only mode but the wagon will only travel about 3km before draining the battery.
Ride and handling
Lexus extended the wheelbase of latest RX by 50mm in a move rumoured to allow for a seven-seat configuration but instead gave more spacious rear legroom.
The platform is similar to its predecessor with some dimensional tweaking working with refined suspension components to return a more composed ride.
Other changes to the design are aimed at making the wagon better for occupants.
The width is up by only 10mm though the height is down by 20mm to lower the centre of gravity and improve airflow.
There are also 10mm extensions to the front and rear track, now 1640mm and 1630mm respectively, and a weight gain of about 55kg.
The suspension is a familiar system with MacPherson struts at the front and double wishbones and coils at the rear, though the Sports Luxury (and F Sport) variants add Lexus’ Adaptive Variable Suspension (AVS).
This comprises electronic dampers that counter the effects of yaw and pitch and can even be adjusted by the driver to suit driving style and conditions.
AVS lowers the dampening force on rough roads, for example, to give a smoother ride. Alternatively, the ride can be made firmer and the vehicle body stance flatter by engaging the drive select button on the Sport S+ setting.
AVS complements and interacts with the vehicle’s electronic stability control and the pre-collision safety system by preventing excess body roll or dive during emergency braking.
In practice, the ride is supple with a tendency to feel too soft for any spirited driving. However, the AVS and the manual control of the dampers gives a flat cornering stance.
The only downside is that though there is some added weight to steering wheel feel when switching to Sport S+, the wheel remains lifeless with little driver feedback.
But there was no criticism from occupants about the quietness and comfort of the ride. Even becoming a passenger in the rear was a treat as we became impressed with the spaciousness and seat comfort, flat floor design and available airvents.
Safety and servicing
Lexus, unlike its parent Toyota, has no capped-price service program. It does have a menu-based program that is transparent to owners. Servicing is required annually or at 15,000km.
The company has a four-year or 100,000 kilometre distance warranty. This compares with most rivals that have a three-year and unlimited distance program. Given the average distance travelled per year by an urban-based car is about 12.000km, the Lexus offer is more comprehensive.
Lexus has a strong name for safety and the RX450h – especially in its flagship Sports Luxury version – does not disappoint.
Standard equipment includes autonomous emergency braking with cameras at the front to avoid stationary and mobile objects and even pedestrians.
There is a 360-degree camera with park sensors, lane departure warning, blind-spot monitor, rear cross-path traffic alert and 10 airbags. It has a five-star ANCAP crash safety rating.
The outside mirrors are heated to prevent frosting, the headlights – and tail-lights, daytime running lights and fog lights – are LED, and there is the clever active shadowing that masks cars ahead to prevent glare at nights.
Glass’s Guide estimates that the RX450h will retain 58 per cent of its purchase price after three years. Some negativity with hybrids remains in the market and this is why the RX450h has less retained value than, for example, the RX350 petrol-only model at 61 per cent.
It’s a better hybrid and one that fulfills all the green demands of discerning, luxury-vehicle buyers.
The Lexus RX450h Sports Luxury is very well equipped and beautifully built and though the driving experience is not particularly sporty, the ride comfort and serenity of the cabin will impress every occupant.
But it is expensive and there may be better value in the petrol-only RX350.
Worse, the list of competitors is increasing.
Jaguar F-Pace 35t S from $103,420 plus on-road costs
Freshly hatched Jaguar SUV looks great on paper with XF 3.0-litre V6 supercharged performance to crank 280kW/450Nm for a 0-100km/h sprint of 5.5 seconds – the quickest in this comparison. Fuel use is 8.9 L/100km. The Jag is neat, reasonably well-equipped and with an adequate safety kit but doesn’t match Lexus or Mercedes. Boot space is liberal at 650-1740 litres, especially given this is the smallest here.
Warranty is three years or unlimited distance.
BMW X5 xDrive35i from $109,900 plus on-road costs
Perennial favourite from BMW still gets it right. The SUV gets a 3.0-litre V6 petrol with 225kW/400Nm thanks to a turbocharger and has an 8.5 L/100km consumption. Performance is 6.5 seconds to 100km/h. It has a three year or unlimited distance warranty. The boost size is 650-1870 litres and the tow rating is 2700kg.
Mercedes-Benz GLE400 from $109,900 plus on-road costs
The German uses a similar powertrain to its peers though the bi-turbo units on the 3.0-litre V6 deliver 245kW/480Nm – the most powerful here – for a 0-100km/h time of 6.1 seconds. Fuel economy is a heavy 9.3 L/100km, partially because this is the heaviest SUV in this comparison. It has a boot area of 690-2010 litres (the biggest) and a tow rating of 3500kg (also the best). Warranty is three years or unlimited distance.
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