Lexus GS Hybrid

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Auto Trader NZ
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Published 3 September 2020

After driving the Lexus RX400h last year I know you can have your automotive cake and eat it too. You can have eco-friendly tech without the hair shirt; you can have tyre-smoking performance without paying the fuel penalty. The 450h offers the same body, the same engine and  the same luxury as the RX330, but with a 0-100km/h time that’s half a second quicker. And after a couple of weeks of driving over mountain passes, round town and on motorways the car had achieved 8.7 litre/100km fuel. That’s more than the Lexus’ claim of 8.1 overall, but substantially less than the 12.3 overall claim for the standard petrol version of the luxury SUV.

So what? So a Lexus hybrid has gone on sale in NZ. No, it’s not a 4WD – it’s another variant of the excellent GS sedan. We’re told the tech needed to seamlessly integrate hybrid into a rear-drive car was interesting – though why it should be any more interesting than seamlessly integrating two electric motors and all-wheel drive into the RX wasn’t clear. But let’s forget cynicism for a moment – this is a very clever bit of kit. The 3.5-litre 60-degree V6 petrol engine is based on the GS300 unit, but bored out to 3456cc. The dual VVTi variable valve timing system uses both port and direct injection – singly or combined, depending on driving conditions. Direct injection operates at idle or at high speeds, with low-speed or low-torque conditions employing both to optimise the fuel/air mix.  This petrol unit alone puts out 218kW at 6400rpm and 368Nm at 4800rpm. Then there’s the electric engine. Mostly it’s similar to Prius, with a planetary gear unit, an inverter and a hybrid battery – but here there’s also a two-stage reduction mechanism which alters its operation according to driving conditions. By doing that it offers the best of the urge all the way from start-up to top speed.  But first, electric motor one starts the petrol engine, and doubles as a generator to charge the battery. Electric motor two drives the wheels – adding 147kW at 5615 to 13000rpm, and 275Nm anywhere from zero to 3840rpm.

Given that electric motors make the best of their torque at the low end of the range they usually run out of breath as speeds rise. But at about 3000 or so rpm the two-stage reduction planetary gear unit drops the gearing to offer the GS a second wind, so to speak. The urge on offer goes to the rear wheels via a CVT gearbox, so in theory the driver doesn’t have to change gear. But it’s a Hybrid Sequential Shiftmatic. Tap the conventional gear lever to hold the revs – thus increasing engine braking and, therefore, power regeneration.  You can use it to accelerate harder, but given the efficiency of CVT there’s no point – except to increase engine braking on long downhills.

All that tech making you nervous? You can forget about it and just drive. The hybrid’s fancy cooling system won’t need touching for 10 years; hell, the battery’s guaranteed for eight, and is expected to last 12 years or so. At which point it doesn’t cause landfill problems – for Lexus will pay to get the batteries to head office, and thence to France for recycling. Payback for all that nuclear waste France ships to the Pacific, perhaps?

This stuff will be rolled out across all Lexus products within five years, arriving in the RX and LS within the next 12 months. And it’ll be popular, for luxury car buyers want to be responsible – or at least seem responsible – without making compromises. In this case they want the fuel economy of a 2.5 with the performance of a V8. Is that what they get? Well, they certainly get the luxury, for bar small differences to the instrument panel and the information screen – so you can keep track of what the motors are doing should you wish – the interior is standard GS. That means lashings of leather punctuated by polished wood and touches of chrome. That means almost every automotive convenience known to mankind, and high attention to detail and build quality.  That even means a useable boot – the battery does cut space to 280 litres but, yes, you can still fit two sets of golf clubs back there.
It also means performance, albeit without the throaty V8 soundtrack. This car gets from zero to 100km/h in under six seconds, from 80 to 120 in under five. It offers 22 percent more power than the V8, while using 30 percent less fuel – Lexus claims 7.9 litres/100km. Get the petrol and electric motors working at maximum effort and they’ll throw out 253kW to the V8’s 208. There’s no tacho – it’s irrelevant when the engine could be idle without your slowing down. That’s the reason for the power meter, which shows you how much of the 250kW you’re using – or how much you’re regenerating. And as for torque, well, that gets a little complicated thanks to the effects of the reduction gears – high range reduction offers the equivalent of 522Nm; low range reduction delivers the equivalent of 1072Nm. But forget the numbers. Just take our word for it – plant your boot and this thing gets up and goes. It may not offer the gut-tingling roar of a V8 on the charge, but most luxo barges are too well insulated to hear that evocative roar anyway. What you get in this GS is rapid acceleration without as rapid a rise in fuel bills.

Quibbles? Not many. If you want to tow you’re fresh out of luck – we’re rated as Australian, and the hybrid’s fancy cooling system couldn’t take the strain of Queensland summers and boat trailers. Toyota NZ is working on it.
Otherwise this really is a win-win car; power with responsibility; chocolate without calories; the cachet of complicated tech in a package the stereotypical empty-headed blonde could control. Toyota put its first hybrid on sale in 1997, and cumulative global sales now stand at 500,000. Toyota plans to sell a million hybrids each year by 2010, and that’s just the thin end of the wedge, for it’s sharing hybrid tech with Ford, Nissan and GM – and thus most of the industry, for those names embrace a horde of smaller marques. Think Renault, Holden, Jaguar, Volvo. With fuel prices rising and $200 per barrel no longer a pipe dream, developing a viable and affordable alternative is increasingly important. Maximising hybrid possibilities as a bridge to that alternative future is a certainty. And with this GS, a luxury hybrid that offers old-fashioned acceleration from new-fangled fuel-friendly tech is already here.