Lexus 600hL

You glide along, serene and immensely comfortable in a space separated from that around it. Rather like being in a detached bubble, in fact.

The road may be imperfect; you don’t feel it.

There may be the noise of trucks and cranes and aeroplanes; you don’t hear them.

There is a sense of being in something other than a car, in being moved by a new form of transport. The refinement is simply staggering, the comfort extraordinary.

Yes, here in Australia you’ll pay a quarter of a million dollars for the privilege, but you’ll also be getting one of the most amazing cars to ever roll down a road. The Lexus LS600hL redefines the whole concept of a car.

Lest you think that latter statement is simply hyperbole, consider.

The Lexus has a state-of-the-art 290kW 5-litre V8 – and also a 650 volt electric motor developing 165kW. Combined, the peak power is 327kW - and the driveline has simply enormous torque. The 600hL uses an electronically continuously variable transmission (with a manual over-ride giving eight ratios) and a Torsen differential all-wheel-drive system.

If that isn’t the most sophisticated automotive driveline in the world, we don’t know what is.

It has LED low beam headlights that steer with the front wheels, a radar proximity cruise control that – especially with the regenerative braking possible with the electric system – makes keeping station with other traffic an effortless doddle. It has adaptive air suspension, variable ratio electric steering and a suite of safety features as long as your arm.

In the four seat version (as tested), it even has a rear seat that reclines, extends, and massages your back.

Oh, and performance? This 2.4 tonne vehicle can accelerate to 100 km/h in a claimed 6.3 seconds and yet has a government tested fuel economy of 9.3 litres/100km. On a country drive it can easily do better than that.

But the LS600hL also has some glaring deficiencies.

The steering is bizarrely light and the ratio around centre soporific. The entertainment and navigation electronics seem more fitted to a car of a quarter of the price, and for the market being chased, there are some amazing omissions. The boot is ridiculously small – in fact, smaller than many cars of half the size – and some of the standard features cross the boundary from being effective to being gimmicks.

So let’s see how the car works as an integrated, on-road package.

(Note: the LS600hL is such a complex car and is equipped with so many features that this story does not attempt to cover them all. Please see the download at the end of this story for the complete Lexus press release on the LS600hL – all 18,000 words of it.)

Step into the car and pull the door shut – and well, you don’t have to actually do that. If the door – or boot – is on only the first latch, it will electrically close itself. The point? Little, we think...

Like most of the other Lexus and Toyota hybrids, the LS600hL is started with a pushbutton – you need only have the ‘key’ in your pocket. In many starting conditions (eg if the petrol engine is warm) the petrol engine will stay off – but electric power is immediately available. The car will drive through carparks and the like on electric power alone, but put your foot down and the V8 starts. In urban conditions the petrol engine switches itself off a lot – but as it is literally impossible to tell from within the car whether the V8 is running or stopped, it matters little to the driver how the propulsion is being provided.

Accelerate hard and there’s an unexpectedly brilliant V8 growl – normally inaudible, the engine comes to life as it hurls the huge car down the road. Acceleration in all but one condition is strong: the variable transmission and massive on-tap torque giving a fantastically long shove in the back.

But – and it’s an important deficiency – acceleration off the line is initially quite weak. In fact, plant your foot from a standstill and you can count ‘one-and-two’ before the car really gets going. It’s a sufficient impediment that quick turns across traffic, or selecting a short left-hand lane at traffic lights, are best not done.

Less obvious but still present is another hesitancy – this time when you sharply lift the throttle. In that situation, a slight ‘dash-pot’ effect can be felt.

With a car of this mass and power, fuel economy is highly dependent on driving style. In typical heavy traffic Sydney conditions, air conditioning running and the car being driven as you might expect when chauffeuring, it got 12.3 litres/100km. On a drive that included a mix of city and freeway conditions, it returned 9.5 litres/100km. And, finally, on a long country road trip that included climbing (and descending) the Blue Mountains, it returned 8.4 litres/100km.

Those figures are in the order of 20 per cent better than would be achieved by a petrol engine car of similar size and performance; a diesel might do as well but no current diesel in this class has similar performance.

However, for us the greatest benefit of the hybrid system was not the performance/economy compromise.

As alluded to earlier, the regenerative braking works superbly at progressively slowing the car, especially when the radar cruise control is switched on. When braking manually, the huge ventilated discs (357 x 34mm at the front with four-piston callipers, and 335x 22mm disks with two pot callipers) and regen braking (we saw a peak of 50kW on the dashboard instantaneous power read-out) are matched to a pedal with excellent feel. The level of retardation – helped of course by the huge 245/45 tyres – is never in doubt.

The other enormous benefit of the hybrid system is the instant torque availability. Except for that pause off the line, the 300Nm available from the electric motor and the 520Nm peak from the petrol V8 result in absolutely effortless, wafting performance.

Finally, especially in slow conditions, the hybrid system helps provide an unparalleled level of refinement, principally in the lack of noise. Driving down a narrow, quiet lane, we came up behind a family walking down the middle of the road. Running on electric power alone, the LS600hL was so silent that despite the car being only five or so metres behind the group, it took many seconds before they realised there was a car present.

Ride quality is supremely good. Three adjustable damping levels are provided but in most driving conditions, we left the control set to ‘normal’. The seats have numerous adjustments and are wonderfully comfortable. The air suspension uses a host of active controls that result in the car having little dive, squat or roll. Turn into a corner and the Lexus grips very well; exceed the high levels and the stability control intervenes, its action indicated by beeping from the instrument panel. Throw the car around like a sports machine and we’re sure that the limits would more easily be reached – but who would buy this car to do that? In short, the grip, handling and ride are all well up to the required levels.

But the same can’t be said about the steering. Eerily light, it lacks feel and around straight-ahead can be disconcertingly bad. Watching a new driver at the wheel on a freeway it was interesting to see their unsure, constant small applications of steering lock – it’s hard to tell where you are on the road and that’s certainly not good in what is a very large car. Get onto a tight, heavily trafficked suburban road and panic can start to intrude – more than once we used the immense power to accelerate away from trouble rather than steer through it. We can’t see any driver liking the steering, but if Lexus engineers believe it to be right, then at least a dashboard button that varies the weight and ratio of the steering should be fitted.

Unlike some systems, the continuously variable transmission (intrinsic with the hybrid approach taken by Toyota / Lexus) works with seamless brilliance. Typically (when running!) the petrol V8 is operating at less than 2000 rpm – and is often at 1000 rpm. Eight manual over-ride ratios are provided, but for most drivers, we can’t see these ever being used. Often, a manual over-ride is used to engine brake, but with the automatic regen braking that occurs when the cruise control is in operation, even this potential use is diminished.

But in many respects, the interior is disappointing. No, not the trim or the space, but the features. A large colour LCD screen is positioned mid-dash and this can display navigation, over-ride controls for the climate control and audio systems, and detailed fuel economy statistics. A rear drop-down LCD screen is also fitted. But none of these systems really live up to the promise of a quarter of a million dollars.

The navigation system – a Lexus generic system – is poor. The voice instructions are repetitious and often contradictory (an actual example: “The freeway is on the left” followed without pause by “The freeway is on the right”); the interface is not intuitive and prevents the input of any data (even by the passenger) when the car is moving; and the navigation system can be quite slow to react.

The DVD system does not allow front seat passengers to listen to a separate audio source while the rear seat occupants watch a DVD on the rear screen and listen on earphones – something common in aftermarket systems costing (in relative terms) nearly nothing. The front screen cannot be used for on-the-move monitoring of the rear screen DVD, so for example a front seat passenger cannot easily insert a DVD and get it running for the rear passengers – and since the DVD slot is in the front, the rear passengers can’t do it for themselves.

There is no web access at all – something that surely any business person would want and expect in a car of this cost. In fact, in terms of a chauffeured rear seat business person, the facilities are poor. There’s no fold-down table for a lap-top or even on which to write notes (a small, poorly placed folding table is provided - it’s of near zero use); the DVD screen cannot be used as an extension screen for a lap-top; there’s no in-car PC; there’s not even TV reception.

Given the extraordinary sophistication of other parts of the car, you’d expect the Lexus to be leading in this area of in-car electronics, not trailing the aftermarket.

The switch-gear in the cabin also looks unexpectedly cheap. The rear vision mirror controls, for example, appear to be straight out of a Corolla. Yes, they work fine and are well labelled, but surely in a car of this expense you expect bespoke, integrated switches?

The fuel gauge is also poorly designed - it's rotated so that when the needle appears to be at the half-way point, it’s actually at about one-quarter. This design glitch really intrudes because the rest of the instruments – including the LCD in the centre of the instrument panel – are so clear.

So what to make of this amazing machine?

We think that in the areas that are the most difficult to achieve, Lexus has produced an extraordinary car. It has probably the world’s best cabin refinement, superb performance and – in the context of such a large, powerful car – amazing fuel economy. Its ride and handling are both excellent, and the build quality is almost beyond criticism.

However, the boot (just 330 litres!) is tiny, and the in-cabin electronic features need a major upgrade.

But overall, this is simply a stupendous car of breathtaking on-road competence.

The Lexus LS600hL was provided for this test by Lexus Australia.