TURNING GREEN
ISUZU HAS USED NEW AND TOUGHER MANDATORY EXHAUST EMISSION STANDARDS AS A SPRINGBOARD FOR A RAFT OF UPGRADES TO ITS FAITHFUL D-MAX.
NOVEMBER 2016 saw the introduction of Euro 5 diesel exhaust standards in Australia, replacing the previous Euro 4 standard. What that means is that cars built post November 2016 need to comply with the new standard or they can’t be sold. That’s the law – simple as that.
Euro 5 primarily targets particulate matter in the exhaust gas, so it’s no surprise the D-MAX – previously only certified to Euro 4 – gains a diesel particulate filter (DPF); although, this is by no means the only change. In fact, just about everything bar the bottom-end of Isuzu’s long-serving (from 2005) 3.0-litre diesel engine has been updated, with a new-generation higher-pressure commonrail injection, a new variable-geometry low-inertia turbo, a larger EGR cooler and new pistons the key changes.
There’s also a new Aisin six-speed automatic replacing the Aisin five-speed. And, as with the outgoing five-speed, the new six-speed is also used by Toyota in the Hilux and Prado and shares ratios including the two – notably tall – overdrives. The rear differential has also been strengthened, but it carries the same final-drive ratio.
Outside of these mechanical changes there’s a new interior with bigger touchscreens – seven or eight-inch (with sat-nav), depending on the model – two extra speakers (bringing the total to eight) across the dual-cab range, and more cabin soundproofing. Changes to the exterior include updated lights, bonnet and grille, which contribute to fractionally less aerodynamic drag – according to Isuzu.
POWERTRAIN AND PERFORMANCE
DESPITE the raft of engine changes made, the maximum power output remains at a modest 130kw. So, pedal-to-the-metal, the new D-MAX goes about as hard as the old D-MAX, given the new six-speed only adds an extra overdrive for more relaxed highway cruising.
Away from this extreme, the D-MAX’S engine remake provides more driveability with increased torque (430Nm, up from 380Nm), providing more power at low and middle rpm. The ‘fatter’ torque curve means the previous maximum of 380Nm is produced 100rpm lower (now 1700rpm) and extends 700rpm higher (to 3500rpm).
Effectively, what you get is a more responsive engine and a gearbox that does everything better, though it doesn’t give tighter ratios. The shifts are quicker and slicker than before, and new shift protocols mean a more active and sporty approach to gear selection compared to the generally sleepy five-speed. The auto downshifts on descent – with and without brake intervention – are particularly welltimed. The D-MAX carries the two very tall top gears surprisingly well and doesn’t shuffle back and forth between them on undulating country roads too much.
The new common-rail injection system makes the engine quieter than before; although, the D-MAX’S general engine-running refinement isn’t anything special.
The fact it’s a ‘big’ four-cylinder by class standards and it still runs a relatively high 17.3:1 compression ratio both work against it. By comparison, the 2.8-litre diesel now in the Hilux is smaller in capacity and runs a much ‘softer’ 15.6:1 compression ratio.
The changes have brought a small improvement in the official ADR fuel-consumption figure, down from 8.1L/100km to 7.9L/100km for the two respective automatics. On this test, the D-MAX used 12.0L/100km, which was slightly higher than expected given the D-MAX has generally been one of the more economical utes.
ON-ROAD RIDE AND HANDLING
AS before, the D-MAX’S suspension provides a decent ride that can be surprisingly comfortable, even when the vehicle is unladen. The front-to-rear suspension match that’s often a problem with utes is also well-sorted. It’s also worth noting that the LS-T, as tested here – along with the LS-U and SX models – have ‘standard’ rear springs, while the LS-M utilises ‘heavy duty’ rear springs. Not that it matters much, with only a 25kg difference in payload.
Along with its good front-to-rear suspension match, the D-MAX has a nice, positive steering feel, without having the excellent response and feel of something like the Amarok or Ranger, the class leaders in this regard.
OFF-ROAD
THE D-MAX is a little unusual among today’s utes, as it doesn’t come with a rear diff lock. Nor does the chassis provide anything special in the way of wheel travel, so it’s not among the front runners when it comes to more arduous off-road work, especially gnarly hill climbs.
That said, clearance is up there with the best in class, and it has a particularly good driving position in terms of forward visibility. Plus it’s up to most recreational off-road driving, even on the standard, road-biased tyres.
CABIN, ACCOMMODATION AND SAFETY
ALL D-MAX dual-cabs come with fivestar ANCAP safety, thanks to six airbags and mandatory features like electronic stability control.
In terms of size, the D-MAX’S cabin is bigger than the Hilux, Triton and Navara and matches the Colorado, but it’s not as big as the Ranger, BT-50 or Amarok. It doesn’t matter for the driver or the frontseat passenger, but those in the back will feel the difference, especially when trying to accommodate three adults.
The new cabin also presents better than before. Thankfully it’s much less commercial and more passenger-car like. However, it still doesn’t offer tilt-and-reach steering wheel adjustment.
PRACTICALITIES
THE D-MAX offers a class-leading 3500kg tow rating and class-competitive payloads, even if its GVM is below the best in class. When subjected to our maxxed-out load and tow test (before this recent upgrade) the chassis coped well, but the engine was off the pace; although, no doubt the extra power at low and middle rpm, thanks to the extra torque, will help here.
In the tub there are four tie-down hooks – the two at the rear are mounted on the floor where they should be, but the front pair are high-mounted, which, when used in reality, is hardly useful unless you’re carrying something tall.
The engine draws its air from the inner mudguard, which is great for fording water. As a bonus, there are two recovery hooks up front and a solid engine protection plate. Under the bonnet there’s also room for a second battery. D-MAX’S also come with fully interchangeable 16-, 17- and 18-inch wheels, so there are plenty of options for replacement tyres.