Isuzu MU-X vs Audi RS Q8

What's the difference?

The MU-X has plenty of appeal as a daily driver – dependable and it’s a proven 4WD wagon.

Does the 2.2-litre engine add anything substantial to the mix?

Well, it's better than the 1.9-litre, that's for sure, and there's a lot to like about this MU-X in terms of its off-road capability, driver-assist tech, standard features and all-round driveability. And, while the LS-T lacks the top-shelf polish of the X-Terrain, it’s still an appealing potential purchase.

But the 3.0-litre option is better because while the 2.2L is very effective off-road and general day-to-day driving, it lacks grunt and has to work that much harder and is that much noisier under load than the 3.0-litre in most driving scenarios, including 4WDing.

The Audi RS Q8 Performance is a lot - of everything. It offers lots of power, lots of performance, lots of space and lots of luxury. But it’s also a lot of money, and at more than $250k it’s not going to be on everyone’s shopping list. It’s a very niche proposition for a small group of buyers. For those select few, those who want a lot of everything and who crave the ultimate of whatever product they’re buying, then the RS Q8 Performance is going to be a very tempting proposition - even if they never set any lap record in it.

Note: CarsGuide attended this event as a guest of the manufacturer, with travel, accommodation and meals provided.

In terms of appearance, the MU-X remains largely unchanged from the most recent iteration. And that’s a good thing. It’s blocky enough to be recognisable but sleek enough to remain inoffensive. Worth noting the door handles, window trims, front fender accents, roof rails, and side steps on the LS-T are gloss black.

Inside, nothing much has changed (other than a newly-introduced idle start/stop button) and, as such, the MU-X retains a low-key familiarity that makes it a comfortable space. Generally, design-wise, the MU-X more than holds its own against the likes of the Toyota LandCruiser Prado and Ford Everest.

We don’t refer to ‘facelifted’ cars for no reason, the RS Q8 Performance has a number of visual changes.

These include a new Audi ‘singleframe grille’ and new front bumper design, with a new Matt Carbon trim package available to highlight that.

There’s also a new rear bumper design as well as new digital daytime running lights at the front and digital OLED lights at the rear.

The unique forged alloy wheels are another design change, but also bring a functional element. Measuring 23 inches they do a good job of filling out the wheel arches and give the RS Q8 Performance a purposeful stance and good proportions. But they are also 5kg lighter per wheel than the 22-inch rims on the RS Q8, saving unsprung weight to help the ride and handling.

Inside, Audi hasn’t made any dramatic changes to the design, which is fine because the brand does some of the best cabins on the market in terms of look and feel.

What is new is an aluminium inlay and an optional RS interior design package which provides a unique finish to the seats, with contrasting stitching, for an additional $4100.

The interior has a familiar and practical feel about it and the cabin is an easy space in which to become comfortable. Controls are easy to locate and operate and charging options are numerous – a mix of USB-A, USB-C (front and second row) and 12V.

Storage places include recesses for the bits and pieces from your pockets, a deep-ish 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 also cupholders either side of the third row.

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

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

My camera guru/photographer/sergeant-at-arms, Glen Sullivan, reminded me that the third-row seats don’t have ISOFIX or top-tether points for child seats. Thanks, mate.

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 stowed away.

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. The MU-X’s full-size spare (bravo!) is attached to its undercarriage.

While it’s easy to get swept up in the power and speed of the RS Q8 Performance, it’s important to remember that it’s an SUV and it needs to offer ‘utility’ as well as ‘sports’. 

With that in mind, the front seat occupants are well looked after with supportive and comfortable sports seats, with a good amount of small item storage spaces. 

The rear seats are surprisingly comfortable, despite the sloping roofline of this ‘coupe-style’ SUV. Audi has cut recesses into the ceiling to create more headroom, so it will be fine for anyone under six-foot tall. Despite there being five seat belts, this is realistically more of a four-seater for adults, although three smaller kids could squeeze across the back.

There’s also a pair of cupholders, two USB-C ports, a 12-volt outlet and your own climate controls for the rear passengers.

As for the boot, again it loses some volume because it’s not a wagon-style SUV, but there’s still a decent, square floor space with a claimed 605 litres of capacity.

So, overall the Q8 obviously isn’t the most practical version of an SUV, but it does well given its focus on style.

Audi updated the Q8 range earlier this year, with refreshed looks after seven years on sale and a plug-in hybrid powertrain to cater for new demand.

A new RS Q8 is coming later in the year, but the RS Q8 Performance has arrived first to make a bigger impact. It naturally gets a performance boost, but there are some other extras beyond more kilowatts.

These include RS ceramic brakes, lightweight 23-inch forged alloy wheels, Pirelli P-Zero tyres, unique aluminium inlays and a special RS layout for the digital instrument display.

Which is good, because the RS Q8 Performance costs nearly $25k more than the ‘standard’ RS Q8, priced from $255,800 plus on-road costs.

Luckily for a car costing a quarter of a million bucks, there’s also plenty of luxuries too, including Nappa leather upholstery, four-zone climate control and a 17-speaker 730-watt Bang & Olufsen sound system, amongst others.

When you compare it to its rivals on performance terms, in particular the Urus and Cayenne Turbo, the $250k asking price doesn’t exactly look ‘cheap’ but it is good value in comparison.

The Audi is a touch pricier than the BMW X6 M Performance at $250,900, but quite a bit more affordable than the Mercedes-AMG GLE63 S Coupe at $268,900.

This MU-X has a 2.2-litre, four-cylinder, turbo-diesel engine, producing 120kW at 3600rpm and 400Nm between 1600-2400rpm and it’s matched to an eight-speed automatic transmission.

Worth noting the 3.0L MU-X has a six-speed auto and produces 140kW (at 3600rpm) and 450Nm (1600-2600rpm) while the outgoing 1.9L MU-X has a six-speed auto and produces 110kW (3600rpm) and 350Nm (1800-2600rpm).

While the 3.0-litre has always been unstressed in most driving scenarios – even low-range 4WDing – the 2.2-litre feels underpowered. More about that in the ‘Driving’ section below.

The MU-X has a part-time 4WD system which includes a dual-range transfer case (with high- and low-range 4WD) and a rear diff-lock. The driver is able to shift from 2H (two-wheel drive, high-range) to 4H (4WD high-range) while on the move up to speeds of 100km/h. The diff-lock may only be engaged when the vehicle is in 4L (4WD low-range).

The MU-X also has a switchable terrain mode system which tweaks the engine, transmission and traction control to suit the driving conditions. 'Rough Terrain' mode, like a steroids-enhanced off-road traction control, is king of these modes when you’re off the bitumin.

This is the latest iteration of Audi’s twin-turbo 4.0-litre V8 petrol engine - and it’s a beauty.

While this engine is used in a variety of models, for the RS Q8 Performance Audi has taken power to 471kW with 850Nm of torque, which, as mentioned earlier, makes it the most powerful internal combustion engine Audi has ever offered in a production car.

That’s also a big boost over the previous RS Q8, which managed 441kW/800Nm, and is only just shy of the 485kW/850Nm offered by its ‘cousin’, the Porsche Cayenne Turbo GT.

Audi claims that the RS Q8 Performance will launch 0-100km/h in just 3.6 seconds and keep going to an electronically limited top speed of 250km/h. We tried to test the acceleration time on a closed circuit, but driving into a very strong headwind the big SUV could manage only 4.4 seconds - which is still a very quick time given its size and luxury.

The engine is paired to an eight-speed automatic transmission and Audi’s trademark quattro all-wheel-drive system to help smoothly transmit so much power to the road.

Official combined cycle (urban/extra-urban) fuel consumption for this MU-X is 6.7L/100km. The 1.9L MU-X offers 7.4L/100km while the 3.0L offers 7.6L/100km.

Actual fuel consumption on this test was 8.7L/100km.

The MU-X has an 80-litre fuel tank, so, going by that on-test fuel consumption figure, you should be able to get a driving range of about 920km. But remember, your fuel consumption may be completely different to mine because chances are you'll have friends, family pets, sporting equipment, camping gear, the whole kit and caboodle on board. I've only been carrying vehicle recovery gear, MaxTrax, and a first-aid kit, so I haven't had a huge amount of weight on board.

Unfortunately you don’t get the most powerful production engine without some trade-off, and for the RS Q8 Performance that means significant fuel consumption. The official fuel economy rating is a very thirsty 12.2L/100km, but that's the best-case scenario too. If you partake in some spirited driving that unleashes the full potential of the engine will result in a higher rate of premium unleaded being consumed by the big V8. We saw returns in the high teens across our time, but that was largely open road driving, so we’ll reserve final judgement for an extended test drive across more varied conditions.

Thankfully there’s a fairly large 85L fuel tank, so if you can hit the claimed average you can get a theoretical 696km of range.

Before we launch into the off-roading section of this test, it’s worth noting the MU-X has always been decent on-road; composed, reasonably refined (for a 4WD wagon, anyway) and comfortable. And thankfully, with the 2.2-litre engine, not all of those characteristics have been thrown out the window.

It is quite noisy, especially under pressure when you have to do some heavy acceleration or when you have a bit of gear on board. When it has to work that bit harder than it usually does, it can become quite noisy. Admittedly, the 3.0-litre MU-X is also quite gruff, but there's an edge to the roughness in the 2.2-litre that is very noticeable on road.

This MU-X is quite sluggish off the mark, exhibiting a disconcerting lag under heavy throttle from a standing-start. And it’s far from the most dynamic vehicle to drive. But it has a tractability about it that manages to mostly negate these flaws.

Otherwise, the new eight-speed auto deserves credit as it’s slick and smooth in application and feels right at home in this wagon.

Now to off-roading. The MU-X is still very capable. In fact, even with the 2.2-litre engine, it remains one of the better-performing 4WD wagons straight out of the dealership, in terms of pure off-road capability.

The 3.0-litre MU-X is not the torquiest in this segment, but it offers ample pulling power available across a wide rev range – count on peak torque between 1600rpm and 2400rpm – and it delivers that pulling power in an even-handed fashion. The 2.2-litre MU-X has to work harder than its stablemate, and it’s noisier and harsher.

However, those characteristics don’t take away from how effective this MU-X is because it offers impressive off-road performance. It still has a decent amount of low- and mid-range torque, which makes dirt-road cruising and low-speed 4WDing easy.

The MU-X has part-time 4WD with high- and low-range 4WD gearing, a rear diff lock and overall it retains all of that off-road capability the 3.0-litre MU-X has been renowned for – so you don't lose any efficacy there.

The line-up’s off-road traction control system, which once was a bit patchy in its effectiveness, has gone through a couple of phases and it’s been recalibrated/tweaked over the years and it is much better now.

Of course, the MU-X also has Isuzu’s much-vaunted Rough Terrain mode (a form of early-acting off-road traction control which converts lost grip into torque for the wheels with grip), and it is smooth and effective, giving the driver better overall control in challenging terrain.

Some of this MU-X’s listed off-road angles appear shallower than the 3.0-litre MU-X’s – approach: 23.9 (3.0L = 29.2), departure: 26.4 (3.0L = 26.4) and ramp-over: 19.6 (3.0L = 23.1) – but, even if that is the case, it has very similar driving characteristics in low-speed, low-range four-wheel driving to its 3.0-litre stablemate.

If you drive with control and consideration, you shouldn't have any trouble tackling light to moderate 4WDing in this MU-X. It could even, if push comes to shove, handle challenges that may be considered by some to be on the edge of hard-core 4WDing – for a showroom-standard 4WD wagon anyway.

Ground clearance is 235mm and wading depth is 800mm, so there’s an adequate amount of clearance to work.

The MU-X – with a turning circle of 11.6m and a kerb weight of 2130kg (3.0L = 2185kg) – feels quite nimble on bush tracks.

This wagon’s wheel travel – how far the axle can move up and down relative to the chassis – has more than an adequate amount of flex, stretching its tyres close, if not all the way, to the dirt.

A noticeable trade-off is its 20-inch wheel-and-tyre combination, which is best suited to sealed surfaces and so are far from ideal for dirt-track touring. There’s an easy remedy, though. Buy a set of decent all-terrain tyres on 17- or 18-inch rims to replace the showroom-standard 265/50R20 Highway-Terrain tyres. If you are using your MU-X, avoid dropping pressures too much because you’ll risk sidewall pinches and punctures on these low-profile road tyres.

In terms of packability: the 2.2L MU-X has a listed payload of 670kg, whereas the 3.0L version offers 615kg.

The 2.2L MU-X can legally tow 750kg (unbraked trailer) and 3500kg (braked), so theoretically you can tow the same load as a 3.0-litre MU-X. But, as mentioned, the 2.2-litre engine feels underpowered, even in general day-to-day driving, so with a load and/or towing that’s an added burden.

For reference, the 2.2L MU-X has a listed gross vehicle mass of 2800kg and gross combined mass of 5900kg.

Obviously the RS Q8 Performance is all about speed, Audi made its intention clear by sending it to the Nurburgring to set a new SUV lap record for an SUV. But the reality is most owners are unlikely to hit the racetrack in the RS Q8, so what’s it like on the road?

In a word? Impressive.

While the engine is undoubtedly the star attraction offering up so much effortless performance, the RS Q8 Performance wouldn’t be so quick around the Nurburgring or as nice to drive on the road without its highly advanced chassis systems.

It has an array of technology to help it handle, it has active air suspension, adaptive dampers, active roll stabilisation and all-wheel steering, which help to make this big SUV handle like a much smaller car.

The suspension does a remarkable job of providing a compliant ride on such large alloy wheels, while also providing responsiveness.

The handling is certainly helped by the all-wheel steering, which gets the rear wheels to turn in the opposite direction to the fronts at low speed (below 50km/h), but in the same direction at high speed (above 80km/h), making the big SUV feels much more direct when changing direction.

As for the overall experience, that’s helped by Audi’s surprising decision to actually remove some of the sound insulation, which allows you to hear the engine even more than you ordinarily would. This really plays to the dynamic nature of the RS Q8 Performance.

The RS Q8 Performance comes stacked with the full suite of active safety features. These include adaptive cruise control, lane change warning, rear cross-traffic alert and surround-view cameras.

ANCAP rated the Q8 as five stars back when it first launched in 2019 and that rating is due to expire at the end of 2025. However, ANCAP states that it only applies to the 3.0-litre Q8 models, not the V8-powered RS variants.

The MU-X has a six-year/150,000km warranty and seven years of roadside assistance. Unlimited km in the warranty 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 MY24 and later vehicle models (up to 5 years/75,000km – whichever occurs first) – at a flat price of $469 for each service.

Isuzu Ute Australia has a nationwide network of more than 160 dealer sites.

Despite the extra power and fancy new brakes, the RS Q8 Performance costs the same to service as the existing RS Q8.

That means $4690 for Audi’s five-year service plan, and $5720 for the Audi Advantage.

The latter package includes an extra two-year, unlimited kilometre warranty on top of Audi’s five year/unlimited km coverage. It also includes two extra services and two more years of roadside assistance, to keep you covered for seven years total.

That’s good, but it’s still an extra cost when many mainstream brands already offer seven years of coverage as standard.