Isuzu MU-X vs Mazda BT-50

What's the difference?

The MU-X has always had plenty of appeal as a daily driver – dependable, not dynamic – and it’s a proven 4WD wagon.

Some people don't like the noisy, sluggish engine, but I don't mind it because it delivers off-road.

There was already a lot to like about the seven-seater wagon in terms of its off-road capability, driver-assist tech, standard features, and simple all-round driveability, and the X-Terrain – which encompasses all of that AND adds some polish to the mix – is an impressive top-shelf addition to the MU-X line-up. Even if it's so pricey...

The MY25 Mazda BT-50 benefits from its robust Isuzu underpinnings to excel in this dual cab-chassis configuration, particularly with Mazda’s premium heavy-duty aluminium tray as fitted to our test vehicle. Fact is, apart from the big drop in payload required to tow 3500kg (but it’s not alone there) it’s hard to find any major flaws. Overall, it’s an excellent workhorse that would be well suited to a multitude of tradie tasks. 

As I’ve said before, the MU-X has never been particularly exciting or boring in terms of design, just comfortably adopting a low-key, middle-of-the-road type design – sales gold, in other words.

But the X-Terrain has distinctive ‘X’ branding here and there – inside and out – and that adds a subtle class to this variant.

The X-Terrain is 4860mm long (with a 2855mm wheelbase), 1870mm wide (excluding mirrors), 1825mm high and has a listed kerb weight of 2195kg.

It has a wheel track of 1570mm and an 11.6m turning circle. 

Our test vehicle has the exclusive X-Terrain paint – slate grey metallic – which matches well with the X badging, bigger grille design, new headlights, three-tier LED tail-lights, and redesigned wheels.

The interior strikes a stylish note as well with red stitching on the dash, centre console and leather-accented seat trim.

It must be said that Mazda’s stylists did a commendable job with the third-gen BT-50 when it launched in 2020. Five years later it still looks fresh and we’re yet to find anyone who doesn't like its styling, which is in stark contrast to its polarising predecessor.

Its exterior sculpting embodies Mazda’s design language to maintain a strong family resemblance to the popular CX line of SUVs, yet does not detract from the tough and purposeful appearance expected of a 4x4 ute.

The MY25 facelift includes a newly designed front bumper, radiator grille and unique LED headlights. At the rear, pick-up models incorporate what Mazda describes as a ‘mountain-inspired ridged design’ along the bottom edge of the tailgate, along with new LED tail-lights and a larger Mazda logo.

Apart from the mountain-inspired ridged design, also evident on the glove box lid, the latest XTR interior is largely unchanged, blending different shades of grey with satin chrome highlights on the dashboard and door linings, contrasting fabric seat trim, exposed stitching on seams and adjustable centre console air conditioning vents for rear seat passengers.

The interior has a pleasant, familiar and practical feel about it and this is an easy space in which to swiftly become comfortable. 

Controls are easy to locate and operate and charging options are numerous – a mix of USB-A, USB-C and 12V up front, and USB-A for the second row.

Storage places include recesses for your everyday carry gear, a suitably deep centre console, as well as dual cupholders up front, cupholders in the rear fold-down centre armrest and bottle holders in the doors.

There are cupholders either side of the third row in the MU-X for passengers riding back there.

The MU-X has physical-button options to activate some functions (including to switch on the audio system, to adjust volume, access sat nav etc).

Seats are adequately comfortable and supportive through all three rows – yes, even the third row is roomy enough to prevent whining from whoever is stuck back there.

The cargo area is 311 litres with all three rows in use, 1119L with the third row flat and 2138L with the second and third rows folded.

The rear cargo area has a cargo cover, tie-down points, a 12V power outlet, a storage space under the rear cargo area floor and a space for tools inside the driver’s side rear cargo wall.

Our test vehicle’s 1910kg kerb weight and 3100kg GVM results in a meaty 1190kg payload rating. However, that drops to 891kg after you deduct the combined weight of the premium heavy-duty aluminium tray (243kg), nudge bar (9.0kg) and towing kit (47kg).

It’s also rated to tow up to the class-benchmark 3500kg of braked trailer but with its 6000kg GCM (or how much it can legally carry and tow at the same time), towing that weight would require a substantial 590kg reduction in payload to avoid exceeding the GCM.

Even though few (if any) BT-50 owners would need to tow 3500kg, it’s important to be aware of these numbers if the need arose, to ensure the combined weight of your vehicle and trailer does not exceed the legal limit.

The premium heavy-duty aluminium tray from Mazda’s genuine accessories range is a nice bit of kit with its Mazda-branded tailgate decals and mudguards.

The tray is almost square with internal dimensions of 1800mm length and 1777mm width. And it has numerous internal load-anchorage points, external rope-rails and a sturdy mesh-style rear window protector, plus removable ‘quick-lock’ ladder racks with fold-down load retainers up top.

There’s also a 1500mm-long underbody drawer with adjustable internal dividers and a four-stage incremental locking system. An HDP (High Density Polyethylene) 25-litre water tank complete with tap and handwash bottle-holder resides under the right side of the tray, with a sizeable and lockable HDP toolbox under the left side.

The driver and front passenger have comfortable bucket seats and the rear bench is also accommodating, with ample head and kneeroom even for tall people.

However, shoulder room would be tight for three big tradies, so like most dual cabs short of a full-size US pick-up it’s tolerable for short trips as a five-seater but works best as a four-seater for longer drives.

Cabin storage includes a large-bottle holder and bin in the base of each front door and the dash has upper and lower glove boxes, an overhead glasses holder and a pull-open compartment to the right of the driver’s knee for small items.

The centre console has an open tray at the front, dual small-bottle/cupholders in the centre and a small box at the rear with a contoured lid that doubles as a driver’s elbow rest.

Rear passengers get a large-bottle holder and small bin in each door, plus storage pockets on the front seat backrests and a pair of pop-out cupholders in the fold-down centre armrest.

The 60/40-split rear bench seat’s cushions can also swing up and be stored vertically if more internal load space is needed. This also reveals two underfloor compartments with lids for keeping valuables out of sight.

Our test vehicle is the XTR cab-chassis, which is available only with a 3.0-litre, four-cylinder, turbo-diesel engine and six-speed automatic transmission, for a list price of $59,650.

The XTR is an upgraded version of the base model XT cab chassis equivalent which lists at $54,620, so for the extra $5030 you’ll pay for the XTR the standard equipment list expands to include 18-inch machined alloy wheels with 265/60 R18 tyres (and a full-size alloy spare), LED headlights/DRLs/front fog lamps, side-steps and power-fold mirrors.

The XTR cabin also comes standard with carpet, a leather-wrapped steering wheel and shift knob, three USB-C ports and a 12-volt socket, fold-down rear centre armrest, eight-speaker audio with digital radio and wired/wireless Apple CarPlay and Android Auto connectivity.

The cabin has smart keyless entry (with auto central-locking when you walk away from the vehicle), dual-zone climate control and 9.0-inch multimedia colour touchscreen, now thankfully with physical volume and tuning dials.

In addition to the facelifted styling, is updated software for the touchscreen which includes tyre pressure monitoring and various off-road-focused displays. The driver also gets a new 7.0-inch customisable 'Multi-Information Display' (MID).

Our example, finished in optional 'Ingot Silver Metallic' ($695), is also fitted with several items tailored for tradies from Mazda’s genuine accessories range, including a premium heavy-duty aluminium tray ($7888), SP nudge bar ($1432) and 3500kg tow pack ($1389) which combined add more than $11K to the price.

The MU-X has a 3.0-litre four-cylinder turbo-diesel engine, producing 140kW and 450Nm and it’s matched to a six-speed auto.

These form part of a proven powertrain and while the MU-X may not be the most dynamic vehicle to drive – it’s acceleration is sluggish rather than punchy – it has a real tractability that nullifies any other niggles.

It has part-time 4WD, with high- and low-range as well as various drive modes, rough terrain mode, and a rear diff lock.

The BT-50’s drivetrain, shared with its D-Max donor, comprises Isuzu’s proven Euro 5-compliant 3.0-litre, four-cylinder, turbo-diesel that produces 140kW of power at 3600rpm and 450Nm of torque between 1600-2600rpm.

This is paired with an Aisin-sourced six-speed torque converter automatic featuring ‘intelligent’ protocols that prompt downshifting to assist with engine-braking on steep descents (great when towing) and overdrive on the top two ratios optimises fuel economy during highway driving.

It also offers the choice of sequential manual-shifting, which can be handy when hauling and/or towing heavy loads particularly in hilly terrain.

The part-time, dual-range 4x4 transmission features 2.482:1 low-range reduction and a switchable locking rear diff

Official fuel consumption for this MU-X is 8.3L/100km and that's on a combined cycle. 

On this test I recorded 10.2L/100km. I did a lot of high and low-range four-wheel driving, so that fuel consumption is not too shabby.

The MU-X has an 80-litre fuel tank, so going by my on-test fuel consumption figures you could reasonably expect a driving range of about 784km from a full tank. 

Mazda claims an official combined cycle (urban/extra-urban) average of 8.0L/100km and the dash display was showing 10.2 at the completion of our 369km test, which comprised a mix of city, suburban and highway driving of which about one third was hauling a near-maximum payload.

Our own figure, calculated from fuel bowser and tripmeter readings, was slightly higher again at 10.6L/100km but still within the usual 2.0-3.0L/100km discrepancy between official and real-world figures and not bad for a two-tonne-plus 4x4 ute.

So, based on our figure, you could expect a realistic driving range of around 700km from its 76-litre tank.

In previous tests, the MU-X has been fine on road and more than adequate on gravel, dirt tracks, and during low-range 4WDing. But it’s been a jarring, skippy ride on irregular surfaces rather than as composed as it could – and should – have been. The culprit? Firm suspension, over-inflated tyres, too-tight trousers, who knows?

The good news is it seems like Isuzu has ironed out any issues in the suspension, minor or otherwise, because the MU-X is now is a lot better in terms of ride and handling than ever before. 

Off-road, the MU-X has always been a proven combination of its 3.0-litre, four-cylinder turbo-diesel engine, clever six-speed automatic transmission, and an off-road traction control system that's been increasingly well recalibrated through a number of generations. 

The engine is tractable and gruff, it has plenty of grunt and, as long as you're not driving like a complete hoon, you can usually get through most obstacles without a lot of fuss.

It's this mix of mechanicals and driver-assist tech that make the MU-X such an effective 4WD package. And there are a number of reasons for that. 

For one, that engine delivers plenty of torque down low and in the mid-range torque and that's crucial for four-wheel driving. 

And another thing, Rough Terrain Mode – like a beefed-up and fine-tuned off-road traction control – proves very effective because it punches torque to the wheel with the most traction – while wheel spin on tyres that aren't touching dirt is minimised – and that way it keeps the vehicle moving through obstacles with safe and controlled momentum. 

As I’ve noted before though, Rough Terrain Mode is not a magic all-conquering solution, but it is another handy addition to the MU-X’s off-road toolbox.

And the MU-X also has a rear diff lock to back you up – and that's another valuable component. 

The MU-X has approach, departure and ramp-over angles of 29.2, 26.4 and 23.1 respectively.

A listed 235mm of ground clearance is about standard for this kind of wagon but, as I’ve said before, it seems vulnerable in the underbody, side steps and its plastic mud guards. So the underbody may touch dirt, depending on how challenging the terrain is. 

Wading depth is listed as 800mm.

But, as always, with focused driving, you’ll have lots of fun and you'll minimise any superficial damage or scuff marks to the MU-X.

The MU-X has plenty of potential as a touring platform, but, if you’re planning to do any off-roading beyond well-maintained tracks, then get rid of its road-biased tyres and replace them with all-terrain tyres.

The showroom-standard tyres on this MU-X – 265/50R20 Bridgestone Dueler HTs – are okay, but not really up to scratch if tough 4WDing is what you’re keen to do. I’d prefer an 18-inch wheel and tyre package with decent all-terrains.

The MU-X has a full-sized underslung spare and in terms of packability, the MU-X X-Terrain has a listed payload of 605kg, GVM is 2800kg and GCM is 5900kg.

If you are considering using your MUX as a tow vehicle, it's handy to know that it can legally tow 750kg (unbraked) and 3500kg (braked), which is the standard for large four-wheel-drive wagons. 

Be aware though that, as with any other vehicles, once you're towing anywhere near the maximum weight, your payload is greatly reduced.

The cabin is spacious and, with side-steps plus large handles on the front windscreen pillars, it’s easy to climb aboard and find a comfortable driving position.

All-around vision is good and active driver aids like blind-spot monitoring, rear cross-traffic alert and reversing camera instil confidence, particularly when hauling taller loads that block rear vision through the central mirror.

The engine is responsive in city and suburban use, thanks largely to its broad spread of torque across a 1000rpm-wide band from 1600-2600rpm that showcases its useful flexibility. The six-speed automatic has well-spaced ratios and shift calibrations that feel like they get the best out of this engine, either unladen or when hauling heavy loads.

It feels well-planted on the road and displays sure-footed handling if driven at appropriate speeds for a high-riding 4x4 ute, combined with excellent steering feel and responsive braking.

The unladen ride is firm, as you’d expect given the heavy-duty rear suspension unique to cab-chassis models, but the combined sprung weight of the tray and tow bar ensure it’s not too harsh.

To test its payload rating we strapped 830kg onto the load tray, which with driver and half a tank of diesel was a snip under its GVM limit. Even so, the rear leaf-springs only compressing 40mm under this loading, which left more than 40mm of bump-stop clearance that ensured no bottoming-out on our test route.

It hauled this big load with competence and a smoother ride quality, given the large increase in sprung weight allowed the heavy-duty rear suspension to do what it’s primarily designed to do.

There was also minimal effect on steering and braking response and the engine’s ample torque was not phased by this payload, particularly on our 13 per cent gradient, 2.0km-long set climb at 60km/h.

Engine-braking on the way down was also robust, highlighting the advantage of larger displacement engines (3.0-litres-plus) on overrun when restraining heavy loads on steep descents.

It also has low engine, tyre and wind noise at highway speeds, where the engine requires less than 2000rpm to maintain 110km/h thanks to its overdriven top gear with full torque converter lock-up.

This ensures the BT-50 is a comfortable and economical highway cruiser, with average fuel consumption that quickly drops into single figures on long hauls.

It has a maximum five-star ANCAP rating originally awarded in 2020 and updated in 2022 in accordance with D-Max upgrades.

The benchmark safety menu is packed with passive and active safety features highlighted by multiple airbags including full side-curtains and the latest in low/high speed AEB with pedestrian/cycle/motorcycle detection, lane-keeping, blind-spot monitoring, rear cross-traffic alert, reversing camera, trailer sway control, tyre pressure monitoring and much more.

For junior tradies there are ISOFIX child-seat anchorages and top-tethers for the outer rear seating positions.

The MU-X has a six-year/150,000km warranty and seven years of roadside assistance. That warranty is okay in terms of years, but unlimited kilometres would be welcome.

Service intervals are scheduled for every 12 months or 15,000km, whichever occurs soonest. 

Capped-price servicing covers the first five scheduled services for 24MY and later vehicle models (up to five years/75,000km, whichever occurs first) – at a cost of $469 for each service.

Our test vehicle comes with a five-year/unlimited km warranty.

Scheduled servicing is every 12 months/15,000km whichever occurs first.

Mazda’s ‘estimated service cost’ for the first five years/75,000km totals $2547 which is an average of $509 annually.