Isuzu D-MAX SX 2021 Tow Test

While most of the marketing dollars directed at dual-cab 4x4 utes focuses on the big-buck, blinged-up work ’n’ play models, it’s the more down-to-earth cab-chassis variants that end up doing most of the grunt work.

Loaded up with big toolboxes, canopies and other trade-ready contraptions, these are the money-makers for their hard-working owners – as opposed to money pits for owners of many recreational utes loaded up with accessories!

But the vanilla-white, plain-wrapper appearance of modern cab-chassis utes can be deceiving, with plenty of technology, comfort and safety features fitted to top-spec utes filtering down to these entry-level workhorses.

Case in point: the 2021 Isuzu D-MAX SX Crew Cab Chassis.

One of 20 model variants in the third-generation range, the 2021 Isuzu D-MAX SX Crew Cab Chassis 4x4 tested here – the base-grade four-wheel drive, five-seater tradie special – is priced at $49,700 plus on-road costs.

The price includes the 3.0-litre turbo-diesel engine found across the D-MAX range, paired with a six-speed automatic transmission. A six-speed manual is available for $2000 less.

For the money you also get air-conditioning, a reversing camera, automatic rain-sensing wipers, cruise control, multifunction steering wheel, power windows, power-adjustable mirrors and 7.0-inch touch-screen infotainment system with smartphone mirroring, voice recognition, digital radio and four speakers.

However, the SX-grade D-MAX ute does miss out on some power-assisted niceties, with a conventional key start instead of start button and manual air-con in lieu of climate control. The base-grader also gets halogen instead of LED headlights fitted to up-spec D-MAX models.

Our ready-for-work Mineral White test vehicle came optioned up with a heavy-duty alloy side-style tray ($2407) with slide-out rear drawer ($357), a tinted bonnet protector ($199) and rubber floor mats ($190).

It was also ready for towing up to the 3500kg braked maximum with the optional tow kit fitted including 12-pin trailer plug ($1999) and Redarc electric brake controller ($820), boosting the as-tested price to $55,672 plus on-roads.

That’s not to say the 2021 Isuzu D-MAX SX Crew Cab Chassis 4x4 is a show pony in any way.

Unlike the top-spec D-MAX X-Terrain’s glossy makeover, you get more downmarket matte black side mirrors and door handles and 17-inch steel wheels. The hard-wearing surfaces continue inside with mostly hard black plastics, cloth upholstery, vinyl flooring and a urethane steering wheel.

Apart from hiding the dirt and scratches better, the side mirrors were a good fit for our strap-on towing mirrors but the steering wheel was a bit slippery for sweaty hands on hot days.

The crew-cab’s interior presents as roomy and practical, with a driver’s seat set-up that caters to different-sized adults thanks to a sizeable, supportive seat with six-way manual adjustment, and two-way adjustable steering wheel.

There are some good-size storage spaces up front including in the side doors, centre console bin, glove box and open dash shelving, with some door pockets for drink bottles and under-seat compartments for rear passengers.

There’s decent headroom through to the flat rear seats, although three bigger adults might run out of legroom and shoulder-room. The rear seats aren’t adjustable, but the 70/30-split base folds back to create extra storage space on the floor.

Small children are kept in check with two child seat tethers and ISOFIX points. The rear compartment also gets adjustable air-con vents but no electrical sockets, with the USB and 12V sockets located up front above a dedicated spot for a couple of phones.

The 2021 Isuzu D-MAX SX Crew Cab Chassis 4x4 is surprisingly enjoyable to drive for a tough-as-nails work ute.

Brisk acceleration, controlled cornering, progressive braking and decent bump absorption inspires confidence in general traffic, even without a heavy load out back to help settle the heavy-duty leaf spring rear suspension.

The gruntier 140kW/450Nm 3.0-litre turbo-diesel four-cylinder engine combined with a smoother-shifting six-speed auto in the latest D-MAX also delivers a less-truck-like demeanour around town.

With 300Nm available from as low as 1000rpm, the 3.0-litre engine remains a flexible and willing unit across the rev range. While the transmission tends to hold onto a gear a bit longer than before, delivering more urgency around town, it will tick over quietly around 1500rpm in top gear at 100km/h.

No complaints about the speed-sensitive electric steering either, and together with a 12.5m turning circle parking is a bit easier than with some of its rivals. Ride comfort is acceptable around town with the unladen rear only losing composure over rougher surfaces.

Sticking mostly to the ’burbs with some freeway driving, the D-MAX averaged around 10L/100km driving solo, which gave it a range of over 700km from its 76-litre fuel tank.

While we didn’t get dirty this time, the 4x4 D-MAX is more than capable off-road, with user-friendly switches for the part-time dual-range system, hill descent control and new electromagnetic diff lock.

Safety is another strongpoint of the 2021 Isuzu D-MAX range, with all variants qualifying for a five-star ANCAP rating achieved under the latest testing regime.

Helping it reach such a high level is the standard fitment of eight airbags and a raft of new electronic systems including autonomous emergency braking (AEB), post-collision braking, adaptive cruise control, traffic sign recognition, lane departure warning, lane keep assist, blind spot monitoring, driver fatigue monitoring and trailer sway control.

There are no front and rear parking sensors in the 2021 Isuzu D-MAX SX Crew Cab Chassis 4x4, but there’s a rear camera and a rear cross traffic alert feature to warn drivers of potential hazards when backing up.

However, as we found with the X-Terrain, the electronic driving aids can prove more annoying than life-saving at times. The lane departure/assist and forward collision aids in particular are often over-sensitive and intrusive, beeping and flashing in busy traffic and multi-lane roads unnecessarily.

And on more than one occasion it felt like a tug-of-war with the steering wheel as the system struggled to keep the vehicle within the white lines.

On a more positive note, both the rear cross traffic alert and adaptive cruise control, which helps the vehicle maintain a set speed and distance between it and the car in front, worked a treat.

Most of the driver aids can be switched off by scrolling through the trip computer menu, although they will reset when the engine restarts.

Also below par was the image quality from the reversing camera, especially in low light, and the top third section of the display wasn’t visible due to the optional storage drawer, mounted low down on the rear step bumper, partially blocking the rear camera.

The infotainment display is also smaller than the one found on up-spec models, making the native interface more finicky to use. It worked best with Apple CarPlay, via a USB cord, although sound quality wasn’t great.

For the tow test we hitched up a big 2576kg (Tare) Leader caravan. While more than capable of towing a heavy van with its 3500kg tow rating, the tradie ute did struggle at times.

It didn’t feel particularly settled at highway speeds, while strong winds on the day blunted the performance of the torquey 3.0-litre turbo-diesel engine.

The auto was forced to drop back to fifth gear at 1800rpm on the flat stretches, and third or fourth gear to maintain speed up inclines, with little in reserve for accelerating or overtaking.

It felt more relaxed with a tailwind behind, easily settling into top gear at 1500rpm. Engine noise rose with the revs but it was never intrusive, although it’s not as well insulated as the D-MAX X-Terrain.

A relatively light ball weight (just 186kg) could have exacerbated some minor pitching and swaying experienced above 80km/h. As the rig was fairly level when hitched up, more weight out back (the ute has a maximum payload of 921kg) might also have improved towing manners.

The auto automatically downshifts on declines to provide some engine braking, with the option to manually shift for further engine braking in some situations.

All up, fuel economy when towing averaged out at just over 15L/100km, which was reasonable in the trying circumstances.

For those intending to carry a decent load while towing a heavy trailer, it’s worth mentioning the 2021 Isuzu D-MAX SX Crew Cab Chassis 4x4 with options fitted had a kerb weight close to 2200kg, leaving a payload of around 900kg (GVM is 3100kg).

With a GCM of 5950kg and a 2576kg caravan in tow, that left a decent 1174kg for passengers and other gear. However, loading up the van to its 3500kg ATM would have left just 174kg payload – barely enough for four passengers alone!

Given these weight restrictions and our towing experience, a 2000kg-2500kg trailer is probably a safer and more realistic ‘real life’ scenario for many owners.

Speaking of loads, it’s worth noting the ute’s rear slide-out drawer wouldn’t open fully with the test caravan hitched up.

The Isuzu D-MAX has built up a reputation over the years as a strong, tough vehicle for work and play and, with a few minor exceptions, the latest drivetrain, chassis, safety and technology upgrades make a good thing better.

The 2021 Isuzu D-MAX SX Crew Cab Chassis 4x4 we tested was solidly built, with no rattles in or out of the cabin, while the six-year/150,000km factory warranty, with 12-month/15,000km service intervals and capped-price servicing, add to buyer confidence.

But unless you’re prepared to make some modifications for towing, or load up the rear tray for a bit more tow vehicle mass, the D-MAX cab-chassis may not be the best option for heavy-duty towing.

For owners of smaller camper trailers, caravans or trailerboats weighing around two tonnes or less though, it could be just the ticket.

How much does the 2021 Isuzu D-MAX SX Crew Cab Chassis 4x4 auto cost?
Price: $49,700 (plus on-road costs)
Available: Now
Engine: 3.0-litre four-cylinder turbo-diesel
Output: 140kW/450Nm
Transmission: Six-speed automatic
Fuel: 8.0L/100km (ADR Combined)
CO2: 207g/km (ADR Combined)
Safety rating: Five-star (ANCAP 2020)