After nine years of producing its biggest vehicle with the thirstiest engine in Toyota-dom, Lexus has finally sobered up. But is the LX450d too little, too late?

For: Sensible engine, impressive build quality, good tow vehicle.

Against: Works best in places no Lexus owner will surely dare ever go, flawed specification makes LandCruiser donor a better bet.

Score: 2.5/5

IN a release sent out the other day signaling that it has just built its nine millionth hybrid car, Toyota also made mention that it reckoned those battery-electric models had cumulatively saved their owners 25 billion litres of fuel: Enough, theoretically, for each of those cars to travel around the world, and then some.

It’s a nicely-Green calculation, a great crow for brand credibility. Well done Toyota. Here’s something I doubt they’d be so keen to answer –  how much of this ‘saving’ was then squandered by the Lexus LX, that’s the top-line version of the Land Cruiser 200-Series?

Sure, it’s a rhetorical question. Anyone who has experienced it will surely acknowledge the biggest thing bearing a bent-L badge is quite a drinker – maybe only beaten in Toyotadom by the ships that bring the product here.

But, anyway, it’s all changed now, right? The arrival of the LX450d, that is, a version with the 200kW/650Nm 4.5-litre turbodiesel V8 that has been in the donor Landcruiser 200-Series for yonks, is surely the big revision that, if not wholly redemptive, is at least a step toward salvation?

If only it was that simple. Sadly, it is not. At one level, yes, it is brilliant that you can at last buy this rig with a sensible engine. It drives very well with it on road – true, there’s not the huge pull that is provided by 270kW/530Nm petrol engine but neither is it a slug - and will potentially do even better in environments where Lexus off-roader drivers probably never tread but really should.

Although long in the tooth, this powerplant also disproves an early Lexus argument against its implementation, namely that it wasn’t refined enough. Well, tosh to that. Yes, it can be heard when muscling through the muck in low ratio, but the LX is so massively sound-proofed that it is extremely hard to hear anything mechanical in normal circumstances.

As for the fuel burn? Even though it has smaller tank than the LX570, the 450d will range a lot further, and even though the cited economy of 9.5 litres per 100km does seem a pipedream, it is no less fantastical than the 14.4 cited for the petrol.

Either way, even when driven badly, the diesel will present an average that no petrol owner could ever contemplate seeing in anything but freefall. Then again, there are a lot of other like-sized machines out of Europe that do even better still.

All this is brilliant. Yet I wonder, still, if some other factors will also go against LX450d ownership.

For instance, though beautifully constructed and very comfortable, the diesel nonetheless has fewer luxuries than a top-flight LX570.

It still gets full leather, air suspension with active height control and a power tailgate, but misses out on ventilated seats, rear entertainment screens, third-row seating, Mark Levinson audio. The diesel also restricts to 18-inch alloys which look quite puny and almost under-sized when compare to the LX570’s 21-inch footwear.

Crushingly, too, the diesel has five seats to the petrol’s seven. I cannot help but think that is a real drawback at a time when seven-seat SUVs are clearly in ascendancy. It’s quite perplexing why it has a reduced seat count, not least when the Landcruiser 200-Series – which has the self-same engine – has that capability.

There’s been talk that the LX450d is so close to a weight limit that takes the addition of a third row of pews, which is powered in the other variants, would tip it in a vehicle type category that requires the driver to hold a heavy vehicles license, but that’s never been officially confirmed.

So those issues hang over it. There’s another one. The diesel runs with a six-speed automatic whereas the LX petrol has a just stepped up to an eight-stage unit. While both boxes are impressively smooth in their action, commonsense says the latter would have to be an improvement for the diesel.

Yes, these factors do make it a cheaper choice; but does it make this a more cost-effective one?

Though the LX470d’s $159,900 sticker represents a significant saving on the LX570 that, even though it is $15,900 cheaper than it was pre-facelift, still now positions at $179,900, the model also costs $17k more than a top flight LC200 Limited. What would you buy?

Incredibly, on past performance, LX owners might keep splashing out of the least eonvironmentally-friendly option.

History suggests this customer base seems to give no more thought to stickers than they obviously have ever given to fuel burn or residual values.

That being the case, they might simply judge the petrol and diesel on which equips, drives and looks better ... in which case the LX570 might still be tops. Even though, for the sake of the Earth, it really shouldn’t.

Actually, if the LX crowd was truly thinking straight they would surely be looking beyond this vehicle, for it is now definitely feeling dated when measured against more modern fare. Something like an Audi Q7, for instance, does just as good a job with seating capacity and isn’t much different in dimension, yet driving-wise it is patently a less substantial car, with obvious benefits in the overtaking lane and also for range.

The adoption of the latest Lexus frontal design, with its trademark spindle grille and LED lamps, was an inevitable, but it’s just window-dressing that doesn’t do much to disguise how long the LX has been in production. Also, the new face is a big weird in this dimension, the auto equivalent of Heath Ledger’s Joker: Confronting and a bit scary.

More relevant, perhaps, is that the update also delivers a new safety package called Lexus Safety System Plus, which combines the four key safety systems of Dynamic Radar Cruiser Control, Pre-Crash System, Lane Departure Alert and Automatic High Beam for the headlights.

These are obviously useful assists, but the fitout is messy – usual story, buttons all over the place, some in remarkably silly spots.

The LX’s size and weight and effect these factors have on the dynamics should dictate how you drive it anyway; it’s so wide that the lane departure warning seems to spark into action with the slightest steering wheel movement toward either the centre line or the roadside.

So, anyway, the LX is a hugely capable off-road vehicle, and the diesel makes it better, but that’s almost of no consequence: When did you last see one on the dirt?

Lexus always previously said it only produced this model in petrol because that’s what the primary markets, the Middle East and America, wanted. Doing so alienated it in NZ, where diesel has been the preference.

So this is the right engine. It’s arrived late, maybe too late. The LX has always had a loyal following, but it’s never been a big club. With some many like-priced newer attractions in this category, do we even need a vehicle like this any longer? I really have my doubts.