Tow Test: Isuzu D-MAX 2015

In years gone by pub talk would often revolve around the ‘horsepower wars’ played out by the likes of Holden and Ford and their hot shop affiliates.

At its peak HSV owners didn’t have to utter a word to get the conversation started, with the maximum output boldly emblazoned on the rump of their pride and joy sitting in the carpark.

These days as the local car manufacturing industry winds to a halt, bringing an end to heated homegrown muscle car debates, another big numbers game is being played out, but this time driven by the importers of dual-cab utes.

If you hadn’t noticed these four-door workhorses – previously the domain of chippies, brickies and sparkies – have gained a cult following among outdoorsy types: four-wheel drivers, boaties and grey nomads; the latter appreciating the utes’ often outstanding abilities when it comes to towing.

As a result, those in the business of selling these increasingly popular and more passenger car-like, dual cab utes are engaged in a new battle, but this time it’s maximum braked towing capacities rather than tyre shredding neddies under the bonnet in their sights.

The magic number is 3500kg, which is as heavy as trailers can get in this country before requiring an altogether different, less versatile type of tow tug, like an American pick-up or small Japanese truck.

Current members of the three and a half tonne towing fraternity include Holden Colorado, Ford Ranger and its mechanical twin Mazda BT-50.  The Mitsubishi Triton, Volkswagen Amarok and Nissan Navara boast 3000kg, while Toyota’s top-selling HiLux lags behind with 2500kg, but expect that to change when an all-new HiLux lobs down under later this year.

In the meantime the Isuzu D-MAX, which in many ways has a similar, no-nonsense, tough truck demeanour to the HiLux, albeit in much fresher form, recently raised its towing from 3000kg to 3500kg, although seemingly without any major changes to engine or underpinnings.

Last time we tow tested the D-MAX with a 2200kg van, and while up to the job, we wondered whether it would struggle with the full three tonnes. To find out this time around we hooked up a much heavier van weighing around 2900kg.

As we’ve discovered previously, the D-MAX (unladen) is a pretty good thing around town.

While not state of the art, the five-speed auto is programmed to shift into top gear at every opportunity, which improves both fuel efficiency and overall refinement. Around town this still allows for decent pace off a light throttle, aided by peak torque of 380Nm available from 1800-2800rpm.

It also remains relatively quiet on the freeway, zipping along at 100km/h with revs hovering around 1800rpm.

However, this no-fuss, easy going manner goes out the window once a three tonne load is placed at the rear. The gearbox becomes busier as it hunts for the right gear, and revs regularly rise above 2000rpm, increasingly engine din and impacting smoothness in traffic.

Accelerations is also significantly dulled, making over-taking manoeuvres difficult.

Left in Auto mode cruising at 90km/h on a flat highway, we found the transmission constantly kicking down to fourth gear, keeping revs at a high 2200rpm, and resulting in a constant drone that became tiresome after an hour on the road.

Upshifting manually into top gear solves the problem for a few seconds before the transmission quickly over-rides to a lower gear (without, strangely enough, indicating the change in the instrument readout). It would only rarely stay in top gear under very light throttle on flat or downhill sections.

On the upside, the somewhat bouncy, leaf-sprung rear end calmed down a lot with a decent weight on the tow ball, but there was some noticeable pitching when driving at suburban speeds on less than perfect roads.

Fuel wise, the D-MAX averaged a commendable 7.5L/100km ‘solo’, rising to 14.5L/100km towing, according to the trip computer. That would have given a theoretical range of 525km before the need to refill the 76 litre tank. But given our test route comprised mainly flat highway, consider this a ‘best’ result for the towing weight. 

Also bear in mind the significant reduction in payload if you’re planning to tow the full 3500kg. The D-MAX has a payload capacity of 1005kg, Gross Vehicle Mass (GVM) of 2950kg and Gross Combination Mass (GCM) of 5950kg, so towing 3500kg cuts the maximum payload to around 500kg – not much if you’ve got four beefy blokes onboard!

In mid LS-U spec, the D-MAX’s hard-wearing cabin has few luxuries apart from leather steering wheel, air-conditioning, cruise control, driver’s side auto up/down power windows, steering wheel controls, and a fairly basic, six-speaker audio system with Bluetooth audio and phone connectivity.

There’s no touchscreen, and no 12V outlet or vents in the rear (there's one 12V socket up front). But at least the instruments are more legible in bright sunlight that we remember in the D-MAX-based MU-X wagon.

There are most things desired in an off-road ute, including numerous grab handles and rubber mats for the carpeted floors. The tough plasticky interior appears well screwed together, with only one minor rattle during our test, and side mirrors can be electrically folded in to avoid damage on tight bushy tracks.

Decent off-road traction is provided by switchable high and low-range 4WD but there's no locking rear diff or hill descent control, and the 225mm ground clearance is less than some rivals.

Also changed for the better since our last tow test is an extension of the factory warranty to five years/130,000km, and higher five-star ANCAP safety rating.

‘Our’ D-MAX also came with Cosmic Black paint,  hard tonneau lid, nudge bar, side steps, and tow kit, which nudges RRP pricing beyond $50,000 for the LS-U, although it’s still competitively priced.

As regular towers of heavy caravans and boats, we welcome the growing number of three tonne-plus capable dual cab utes. Particularly when there are fewer heavy-duty SUVs up to the job, with the likes of Nissan’s Pathfinder recently going down the soft-roader route.

But as is often the case, the ‘advertised’ tow rating is not necessarily the most sensible, with maximum torque figures often a better indicator of the vehicle’s abilities under severe load.

While the D-MAX is capable of towing three tonnes-plus, the uninspiring manner in which it does it means something like a Ranger or BT-50, with 90Nm more torque, is a better choice if you plan on spending a lot of time towing something big.

What we liked:
>> Willing engine
>> Tough truck credentials
>> Fuel efficiency

Not so much:
>> Lack of torque for towing
>> Bare-boned interior
>> Spartan rear seating

2015 Isuzu D-MAX LS-U Dual-Cab:

Price: $48,300 (plus on road costs)
Engine: 3.0-litre four-cylinder turbo-diesel
Output: 130kW/380Nm
Transmission: Five-speed automatic
Fuel: 8.1L/100km (ADR Combined)
CO2: 213 g/km (ADR Combined)
Safety rating: Five-star ANCAP
Towing: 3500kg braked, 350kg tow ball