Hyundai Santa Fe vs Mazda CX-80

The contenders

Hyundai Santa Fe 1.6T Hybrid 4WD Premium

List price £49,945 Target Price £46,957

Mazda CX-80 3.3L e-Skyactiv D Exclusive-Line

List price £52,475 Target Price £50,140

A decade ago, more than half of new cars were powered by diesel. That ratio has fallen to just one in 17 so far this year. And in the wake of the infamous Dieselgate emissions cheating scandal and the widespread introduction of ‘clean air’ zones that disproportionately affect anything that drinks from the black pump, it’s hardly surprising.

But is it right to dismiss diesel out of hand? After all, there were some pretty good reasons why it was the fuel of choice for so many not so long ago, and many of those reasons are – in theory, at least – still valid today. To find out the answer, we decided to round up two seven-seat SUVs – one diesel, the other petrol – and take them on a 380-mile road trip.

‘Seven’ was decided on as the theme for our expedition because, er, we were driving seven-seaters (sorry, it was the best we could come up with). The plan was to start at our offices in Twickenham, London, with fully brimmed fuel tanks before driving to Sevenoaks in Kent. From there, we’d head to the Severn Bridge (yes, we know it’s spelt differently, but it’s a great place for photos), followed by an overnight stop in Gloucester. The next morning we’d meander back to London via Seven Springs – considered by many to be the source of the River Thames.

Back at base, we’d crunch the numbers to work out how much the trip cost in each car, dive into the likely long-term ownership costs for our SUVs and then, finally, pick a winner.

Representing diesel power is the Mazda CX-80. More than a few eyebrows were raised when the Japanese brand announced that its new flagship SUV would be offered with a whacking great 3.3-litre six-cylinder diesel under the bonnet – a bigger engine than you’ll find in a diesel Range Rover. Mind you, Mazda 

might not have gone completely mad, because it has fitted mild hybrid technology to help boost official fuel economy to almost 50mpg.

The latest Hyundai Santa Fe has an even more sophisticated full hybrid system, allowing it to run on pure electric power for short distances. After that, though, it deploys a 1.6-litre four-cylinder petrol engine, and its official average fuel economy is actually worse than the CX-80’s, at 38.6mpg. That’s still not bad at all for a big and boxy SUV, especially when you consider that petrol is cheaper than diesel at the pumps.

Both cars are lined up in their entry-level trims to keep the price well below that of premium alternatives, such as the Audi Q7 and Land Rover Defender 110. Both contenders are also specified with four-wheel drive, something you get as standard on the CX-80 but costs £2055 extra on the Santa Fe.

Day 1: The long motorway slog

After 220 miles of mostly motorway driving, we began to wonder if the CX-80’s fuel gauge was broken. It was still showing ‘full’ and the predicted range had actually risen from 590 miles at the start of the day to 700 miles. But eventually the needle did start to move south, albeit very slowly. 

We’ll come on to the real-world numbers later, but the CX-80’s 74-litre fuel tank gives it a massive theoretical range of 806 miles between fill-ups. The Santa Fe’s 67-litre tank means a maximum of 568 miles should be possible before a petrol station visit is required. 

That’s still comfortably enough to outlast even the strongest of bladders, of course, and the Santa Fe is the more pleasant car in which to waft along a motorway. Its softer suspension gives it a smoother ride, for one thing; the CX-80 is far from uncomfortable at a 70mph cruise, but you are jostled around more in your seat.

There’s also more tyre roar in the CX-80, although again not enough to really irritate you on a long journey. What might do, however, is the shortage of lower back support provided by the driver’s seat. That’s because entry-level Exclusive-Line trim does without adjustable lumbar support – a bizarre omission when you get luxuries such as a head-up display (which projects information onto the windscreen in front of your eyes) as standard.

The £1400 Comfort Pack (not fitted to our car) adds fully electric front seats with adjustable lumbar support, but without this must-have extra on the CX-80, the Santa Fe has a far more comfortable and supportive driving position. You sit farther from the road – something many drivers will love – and its boxier shape makes it  easier to see out of in all directions. 

Mind you, the CX-80 hits back with a more upmarket interior. Mazda always scores well for interior quality, and the CX-80 is a perfect example of why, offering plush-feeling materials in all the important places. Although the interior design is on the conservative side, build quality is exceptional – something you have time to really appreciate on a long journey.

The Santa Fe doesn’t feel quite as robust inside, and not all of the materials are of the same standard as the CX-80’s, but it’s still better than a lot of mainstream rivals. If you want anything other than a grey interior in either car, you’ll need to upgrade to a posher trim level.

It’s a similar story when it comes to infotainment. The Santa Fe’s 12.3in touchscreen is absolutely fine: it’s easy to see and the menu layout is intuitive enough. The CX-80’s system is even better, though, mainly because you can control it either by prodding the touchscreen (also 12.3in) or using a rotary controller between the front seats. This second method is far less distracting when you’re driving – even on a long, straight motorway, let alone when negotiating busy junctions and roundabouts.

Day 2: Country roads and back to London

After an early breakfast, we headed out of Gloucester and soon found ourselves on some twistier country roads – and the first thing that became apparent was the different ways in which these SUVs deliver their power. The Santa Fe, with the help of its fairly large electric motor, surges forwards the instant you squeeze the accelerator pedal. In the CX-80, there’s often a lengthy pause between pressing the pedal and the car picking up speed. 

The blame lies with the slow-witted automatic gearbox, and the engine’s mild hybrid electrical assistance isn’t sufficient to fill this void. When the CX-80 does eventually get into its stride, though, it piles on speed noticeably quicker than the Santa Fe, and the muscular growl from the six-cylinder engine is far more pleasing to the ears than the Hyundai’s higher-pitched hum.

These cars handle very differently from each other, too. The CX-80’s firm suspension helps to keep body lean in check through corners, whereas the softer Santa Fe sways around more, especially through tighter twists and turns. Then again, at moderate speeds the Santa Fe’s sharper steering helps it to feel a bit more alert and light on its toes, because smaller inputs are needed to get around bends.

The CX-80’s slower steering is still accurate, though, and some drivers will gain extra confidence from its much heavier weighting at higher speeds. Mind you, that weighting does feel rather unnecessary at low speeds; it makes parking more of a chore than in the Santa Fe.

A stop for lunch at the supposed source of the Thames gave us a chance to check out the practicality of our SUVs – something plenty of buyers will argue is even more important than the way they drive. And when just the first two rows of seats are occupied, both offer loads of space. Yes, rear head room is better in the Santa Fe, but a pair of six-footers will be more than comfortable in either. Indeed, leg room is similarly generous when the sliding second-row seats are pushed all the way back.

The Santa Fe’s second row is better at carrying three people, though, mainly because a middle passenger in the CX-80 has to straddle a huge hump in the floor. 

You probably won’t be surprised to learn that the Santa Fe, with such a squared-off rear end, also has more head room in its third row. Even six-footers will be comfortable back there on longer journeys; they’ll fit in CX-80’s rearmost seats but might have to duck their heads slightly, and the seating position is closer to the floor and less comfortable.

The fact that the CX-80 doesn’t have Isofix child seat attachments on its third-row seats is a shame, too. The Santa Fe gets these as standard, meaning you can put a couple of kids right at the back of the car and let grandparents sit on the more comfortable and easier-to-access middle-row seats.

That oblong rear end also helps to give the Santa Fe the edge when it comes to boot space – especially if you’re carrying taller items. The CX-80’s unnecessarily low load cover doesn’t help, although this can be stowed under the floor when it isn’t needed. In the Santa Fe, there’s no space under the floor to stash the tonneau cover when it isn’t required.

With our lunch break over, we got back on the road and 90 minutes later were off the motorway and just a few miles from Twickenham. The Santa Fe remained just as comfortable and agreeable on these beaten-up urban roads as it had been on the rest of the trip, whereas the CX-80’s ride deteriorates at lower speeds and can feel rather wooden – especially over broken patches of bitumen and recessed drain covers.

We arrived back in Twickenham with 377 miles on the clock and the CX-80’s fuel gauge still, astonishingly, reading three-quarters full. Even the Santa Fe’s was showing almost half a tank remaining. All that was left was to brim both tanks and get the spreadsheets out.

The numbers

Over the course of our journey, the CX-80 used a total of 36.16 litres of diesel at an impressive average of 47.6mpg – very close to the 48mpg showing on the trip computer. The Santa Fe’s computer wasn’t quite as accurate; it showed 41.6mpg when the car in fact managed 39.6mpg – although that’s actually better than the official fuel economy. The 43.21 litres of petrol it used cost £63.04 (based on a price of £1.459 per litre) on the day, compared with the £54.93 (at £1.519 per litre of diesel) that we spent on the CX-80.

So, it’s pretty clear that the CX-80 is far more frugal, at least on longer trips – and by more than enough to offset the higher cost of diesel at the pumps. Its impressive fuel economy also translates to a maximum real-world range of 774 miles, compared with the 583 miles you’ll get from a full Santa Fe.

Fuel costs are only part of the story, though. You’ll also want to consider how much each car costs to own in the long run, and despite its thirstier engine, it’s the Santa Fe that works out cheaper. It costs less to buy in the first place, especially after discounts, and yet it’s predicted to be worth more if you sell after three years with 36,000 miles on the clock.

It’s also the cheaper choice if you’re signing up to a PCP finance agreement. Put down a £5000 deposit and you’ll pay £654 per month over the next four years to drive the Santa Fe, assuming an annual limit of 10,000 miles. On the same terms, the CX-80 will cost you an extra £21 per month.

There’s barely anything in it if you’re a company car driver paying benefit-in-kind tax, because the CX-80’s lower CO2 output virtually offsets its higher list price. That said, both of these SUVs are available in plug-in hybrid (PHEV) form if you’re a business user looking to lower your tax bill. We wouldn’t recommend the PHEVs to private buyers, though, because that version of the CX-80 isn’t very good and the Santa Fe equivalent is rather pricey.

Even as tested here in their entry-level trims, you get all the creature comforts you really need (adjustable lumbar support being the notable exception in the CX-80, as we mentioned earlier). The Santa Fe has adaptive cruise control (it’s just regular cruise in the CX-80 unless you pay extra), but has just two climate control zones for those in the front. The CX-80 has a third zone to cater specifically for rear passengers.

We can’t give you much of a steer about reliability, because both cars were too new to have featured in our most recent survey. However, you’ll get extra peace of mind from Hyundai’s five-year/unlimited-mileage warranty than from Mazda’s three-year/60,000-mile cover.

The CX-80 has a better safety rating, though, being awarded five stars (out of five) when tested by Euro NCAP. The Santa Fe managed only four stars in entry-level Premium trim (higher trims scored five) and was found to be less effective at protecting adult occupants in a crash. Both cars scored equally highly for their ability to protect children sitting in the back.

Our verdict

The CX-80 proves that modern diesel engines can combine impressive real-world fuel economy with strong performance, and you needn’t worry about being banned from the UK’s ever-expanding clean air zones any time soon, because all new diesel cars have to meet tough Euro 6 emissions standards.

That doesn’t mean there are no nasties being pumped out of the exhaust pipe, though. The reality is that any car that runs on petrol or diesel – hybrid or otherwise – produces toxic fumes; the only question is how much. Looking at the official data, the CX-80 emits around five times as much fine particulate matter as the Santa Fe and a third more NOx (nitrogen oxides), but also fewer unburnt hydrocarbons and less planet-warming CO2. 

So, the fact that the Santa Fe wins this test has nothing to do with what’s under its bonnet. It’s because it’s better at carrying seven people, has a bigger boot and, in the ways that matter most to SUV buyers, is better to drive. It’ll also work out cheaper in the long run for both cash and PCP buyers, despite the CX-80’s much better real-world fuel economy. In fact, we think the Santa Fe is the best seven-seater on sale today.

Specifications: Hyundai Santa Fe 1.6T Hybrid 4WD Premium

Engine 4cyl, 1598cc turbo, petrol, plus electric motor
Power 212bhp (total)
Torque 271lb ft (total)
Gearbox 6-spd automatic
0-62mph 9.8sec
Top speed 112mph
Official fuel economy 38.6mpg
Fuel used during test 43.21 litres
Test fuel economy 39.6mpg
Test fuel cost £63.04*
Cost per mile 17p
CO2, tax band 165g/km, 37%

Hyundai Santa Fe review >>

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Specifications: Mazda CX-80 3.3L e-Skyactiv D Exclusive-Line

Engine 6cyl, 3283cc, diesel
Power 251bhp at 3750rpm
Torque 406lb ft at 1500-2400rpm
Gearbox 8-spd automatic
0-62mph 8.4sec
Top speed 136mph
Official fuel economy 49.6mpg
Fuel used during test 36.16 litres
Test fuel economy 47.6mpg
Test fuel cost £54.93*
Cost per mile 15p
CO2, tax band 148g/km, 35% 

*Based on petrol cost of £1.459 per litre, diesel cost of £1.519 per litre

Mazda CX-80 review >>

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What are the differences between types of hybrids?

Mild hybrid

This is the least effective type of hybrid technology – but also the cheapest. Most mild hybrids have a 48-volt electrical system consisting of a starter-generator and a tiny battery, which is charged up using energy that would otherwise be wasted when slowing down. This energy can then be used to provide the petrol or diesel engine with a small amount of assistance when pulling away, aiding performance and reducing fuel consumption in the process.

Some of the latest mild hybrid systems, from the likes of Audi and Peugeot, are powerful enough to actually drive the car along using just battery power for very short distances, as long as you’re super-gentle with the accelerator pedal. On the other hand, some of the cheapest mild hybrid models (such as the Suzuki Swift) still have regular 12-volt electrical systems, which provide the engine with only minuscule amounts of electrical assistance. 

Full hybrid

This technology can be a great way to improve fuel economy and reduce emissions – but it’s important not to get carried away by the marketing nonsense that surrounds it. For example, you might have heard full hybrids being referred to as ‘self-charging’ hybrids; this implies that such cars somehow gather electricity from the ether as you drive along to save you the hassle of plugging it in. 

In reality, the battery is charged by burning petrol – either to drive a generator or to directly drive the car along, creating momentum that can then be converted to electricity as you slow down. The energy in the battery is then used to power an electric motor that assists the petrol engine or even drive the car along by itself.

Despite the extra weight it adds, this system usually reduces fuel consumption. However, that isn’t always the case; for instance, we’ve found that the e-Power versions of the Nissan Qashqai and Nissan X-Trail are less frugal in real-world use than regular petrol equivalents.

The short of it is that you shouldn’t automatically assume you’re doing the environment a huge favour by choosing a hybrid. You’re still buying a petrol (or in some cases diesel) car; the only difference is that you’ll hopefully get better fuel economy and lower your CO2 output.

Plug-in hybrid

Plug-in hybrids (PHEVs) have much bigger batteries than regular hybrids, and that means they can travel farther on electric power alone; some of the latest PHEVs can officially cover more than 80 miles without firing up their petrol (or sometimes diesel) engine. And the longer the electric range, the more spectacular the official fuel economy figures are likely to be – although you’d have to plug in regularly and rarely cover long distances to even get close to matching those numbers.

This concept might seem like the ideal compromise between a fully electric car (EV) and a petrol one, but there are some drawbacks. PHEVs are more expensive to buy than equivalent regular hybrids and, because they weigh more, aren’t normally as frugal if you don’t plug them in. Nor can they usually match the efficiency of EVs when running on battery power.

What’s more, because they have two power sources, huge quantities of natural resources go into their production – and that isn’t good for the environment, especially given that studies have shown many buyers rarely plug them in. However, if you’re a company car driver, a PHEV can save you a fortune in benefit-in-kind tax compared with a mild or full hybrid. An EV would be an even cheaper option, though.

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