Hyundai i40 Premium v Hyundai Sonata Premium : Comparison review

Australia’s mid-sized sedan market might be smaller than a few years ago, but Hyundai is one brand that for good or bad remains intent on covering the bases.

In one corner is the recently released Sonata, which we’ve compared favourably against a number of segment rivals such as the Mazda 6 (as you can read here). The version we’re looking at here is the top-spec Premium turbo-petrol powered variant.

In the other corner is the newly upgraded i40 Premium sedan, with its sleeker European-penned lines and, as of last week with the launch of the mid-life update, a diesel engine as its sole powertrain.

Given key rivals such as the Mazda 6 and Ford Mondeo come in petrol and diesel guise, Hyundai’s decision to cover the market with two different cars — one petrol and one diesel — is interesting enough to warrant an inter-brand comparison. This is reinforced by the fact that both now retail for an identical $41,990 plus on-road costs following the i40’s recent price cut.

The choice for buyers now appears clearer. If you want a potent petrol engine and maximum space, dealers will direct you to the Sonata. If you want classy Euro design and a frugal diesel engine, the i40 it is.

But is the choice quite so cut-and-dry?

Pricing and specifications

Both cars tested here are flagship Premium variants, and come generously equipped for their identical $41,990 price tags.

Both share equipment including satellite-navigation, Bluetooth/USB and AUX connections, 4.2-inch TFT displays between the gauges, a reverse-view camera, all-round parking sensors, heated leather-appointed seats, electric park brake with Auto Hold function, proximity key, LED daytime running lights, dusk-sensing headlights, rain-sensing wipers, climate control and a panoramic sunroof.

The i40 comes with a 7.0-inch touchscreen, but the Sonata trumps it with its 8.0-inch unit. Neither comes with the Mazda 6’s superior rotary controlling dial though, and both are positioned at an angle that makes them prone to washout in direct sunlight.

Pictured: Hyundai Sonata.

The Sonata also gets seat ventilation (which was on the pre-facelift i40) and memory settings, electric-folding mirrors and hands-free full boot opening.

Both also come with a full-sized spare, though the Sonata’s 18-inch alloy wheels beat the i40’s 17s.

The i40 in turn has niceties not found on the Sonata including LED puddle lamps, glove box cooling, a lane keeping assist function that nudges you back into your lane and a semi-automated parallel parking assist function called Smart Parking Assist.

It also gets nine airbags to the Sonata’s six. Both are five-star ANCAP cars (albeit the i40 against 2011 ratings, the Sonata against harsher 2015 criteria).

Pictured: Hyundai i40.

All told it’s a close-run thing. The i40 has some clever luxury car touches, but the Sonata’s superior screen is something you’re more likely to appreciate day-to-day.

It’s also worth considering where each sits in relation to the benchmark Mazda 6 GT petrol, which sits one rung below the flagship Atenza, and in petrol form costs $42,790. The diesel version will set you back $45,920, though you can get a lower-spec Touring diesel for $40,480.

The specifications aren’t wildly different, though Mazda commendably offers (for about $1000 extra) a suite of active safety technology missing-in-action on the Hyundais, including low-speed autonomous braking, blind-spot monitoring and rear cross-traffic alert.

Given diesel variants generally cost more than petrols, the (absent) price parity between these two Hyundais looks to be a tick for the i40.


For cars made by the same company, there isn’t much ‘family’ design commonality to be found. There are almost no shared bits beyond the starter button, navigation software and the blue backlighting.

It’s the Sonata that feels immediately more homely. The fascia has a horizontal and ergonomic layout that is slightly driver-oriented. The switchgear looks tidy and uncluttered, and the extra screen space makes a difference.

By comparison, the i40’s narrower and more cluttered instruments are a little too reminiscent of the smaller and cheaper i30 hatch to look as premium as the excellent build quality makes it all feel. It does have lovely dials though, and the TFT screen between them with digital speedo and trip computer is a match for the Sonata.

Both the i40 and Sonata have swathes of soft-touch plastics and silvery trim bits, and both have good glove boxes, consoles, door pockets, cup-holders, closed storage cubbies under the ventilation controls and sunglasses-holders. The Sonata might have the biggest vanity mirrors we’ve ever seen.

Pictured: Hyundai Sonata.

The Sonata also had moderately more comfortable front seats — they’re more like armchairs really — that you’ll love in summer courtesy of their cooling function. That’s not to say the i40’s black leather pews aren’t comfortable.

That said, drivers might find their left knee hitting the Sonata’s lower dash more than they’d like. Furthermore, some of the switches on the doors feel decidedly lower-grade than found elsewhere.

Jumping into the rear seats, the Sonata emerges the winner. The i40 has good rear legroom, but the Sonata’s is simply remarkable. This is despite the i40’s 35mm longer wheelbase (at 1805mm). The Sonata's rear seats are nudging the Genesis for space, really.

Interestingly, the Sonata is 110mm longer overall, meaning it has appreciably larger overhangs. Perhaps that’s why the snub-nosed i40 has what I’d consider to be much nicer proportions? The i40 clearly wins the ‘driveway test’, with its sharper nose design and sleek (German-designed) angles and lines.

Pictured: Hyundai Sonata.

Sonata also offers more shoulder room, foot room under the front seats and more headroom. The i40’s back row makes anyone over 180cm stoop a touch due to the sunroof.

Both models get rear air vents, individual reading lights, good door pockets, and three top-tether child seat attachments (with ISOFIX anchor points standard in the i40 but not in the Sonata - they'll be fitted to cars arriving later in 2015). Both have a flip-down ski port with two cup-holders, though the i40 takes this further by offering a nifty closing section embedded within, too.

The Sonata counters with its window blinds (the i40 makes do with privacy glass) and proper leather-type map pockets (the i40 has flimsy rope-mesh ones).

Both cars also have flip-folding (60:40) rear seats allowing you to carry long items such as flat-pack furniture, but only the Sonata has clever latches in the boot as well as atop the seats to drop them more easily. The i40 counters with a cargo net not offered on the Sonata.

Pictured: Hyundai i40.

Both have significant boots — 510 litres to the Sonata and 505L to the i40 — and each commendably has a full-sized spare under the floor. The Mazda 6 doesn’t.

Under the bonnet

The rationale for Hyundai offering both the Sonata and the i40 are the differences under their respective bonnets. Both engines send power to the front wheels, but beyond that it’s an exercise in contrast: One focuses on pace, the other on fuel consumption.

The Sonata is available with two petrol engines, but the one we’re interested in here (standard on the Premium) is a 2.0-litre turbo with a class-leading 180kW of power at 6000rpm and 350Nm between 1400 and 4000rpm. Matched to this engine is a six-speed automatic transmission with a torque converter.

The i40 sedan previously came in petrol and diesel forms, but to avoid excessive cannibalisation between its models, now only the diesel remains. The re-jigged 1.7-litre turbo-diesel engine now produces 104kW of power (up 4kW on the Series I) at 4000rpm and 340Nm of torque (up 20Nm) between 1750 and 2500rpm.

Also gone is the old auto, and in its place is a brand new seven-speed double-clutch DCT unit with paddles that promises to brings faster changes and greater fuel economy. Hyundai’s claim of 5.1 litres per 100km on the combined cycle compares to 9.2L/100km for the Sonata.

On our combined-cycle route, we managed 9.8L/100km on the Sonata, which is thirsty but impressively close to Hyundai’s claim. Manufacturers typically exaggerate more than that.

On a side note, the i40 Tourer wagon still comes with the additional option of a cheaper 2.0-litre non-turbo petrol engine with 121kW/203Nm.

Given they tip the scales at a similar weight — 1645kg for the Sonata and 1661kg for the i40 — The Sonata’s higher outputs obviously translate to more immediate and punchy performance around town and in aggressive driving.

The 2.0-litre engine is really strong under hard acceleration, with crisp and almost immediate responsiveness. The only downer is the tinny exhaust note, which sounds vaguely diesel-like at low rpm. The six-speed auto is faithful and predictable.

By contrast, the i40’s diesel is impressively refined — few vibrations enter the cabin — but no firebrand. It’s no performance diesel like the Mazda 6’s 129kW/420Nm unit.

Off-the-line punch is subdued, though as with all diesels it’s a fantastic long-distance cruiser, given it’s content to chug along ticking barely over idle.

The decision to add a DCT for its potential fuel economy gains makes sense, though like earlier iterations of the Volkswagen DSG, you notice the odd moment of jerkiness at lower speeds. It can be a little slow to kick down, and won’t do quick successional shifts, but general progression under hard throttle is certainly better than before.

The Auto Hold function irons out rollback too, and the gear-changes on the fly are rapid and decisive as all boxes of this type are.

Day to day, you’ll clearly have more fun with the Sonata, but beware burying the right foot, lest your fuel use rocket up beyond 12.0L/100km. Our time in the i40 yielded a return in the high 6s, with lots of urban driving.

Ride and handling

Immediately obvious after even a few minutes in the Sonata is the impressive way it dispatches bumps, lumps and corrugations at any speed within legal confines. The all-round independent suspension (multi-link) rear and damper tune offers a good balance between quick rebound and bump absorption.

Hyundai’s local suspension team may have sharpened it up a little more than the US model, but there’s still a comfort bias. As there should be.

The electric-assist steering in normal or sport mode is on the light side, but is suitably quick immediately off-centre. Body control and the general handling package is not as surgically honed as the Mazda, but it feels a match for the new Ford Mondeo.

Right off the bat, the i40 feels a touch firmer in the dampers — a little more tied-down mid-corner. The smaller wheels and chunkier tyres negate any of the reciprocal decrease in bump absorption, so it remains comfortable at low speeds. The Australian-developed suspension has been calibrated to offer more low-speed comfort.

Likewise there’s a little more weight in the steering, though nothing more than the simulacrum of proper chatter between the wheels on the road and the one in your hand. Initial bite and body control through bends feels marginally superior, evident in the absence of the odd tyre squeal present in the Sonata over the same roads.

Interestingly, both have identical 2.78 turn lock-to-lock cycles and 10.9 metre turning circles.

The Sonata probably strikes a marginally better balance for the everyday, with supreme ride comfort/bump absorption. Both are relatively quiet and effective cruisers.

Warranty and service

Both models come with the same five-year/unlimited kilometre warranties, sat-nav update plans and up to 10 years of roadside assist (if you service the car at Hyundai). Both also come with life-of-vehicle capped-price servicing.

However, the Sonata Turbo has tiny intervals of six months or 7500km, each visit costing between $159 and $259 until the four-year/60,000km mark, when there’s a $399 service. This is repeated after five years or 75,000km.

The i40 has superior 12-month/15,000km service schedules, with each visit generally costing $339 or $439 until bigger $475 and $500 visits after six years/90,000km or six years/120,000km.


In some cases, these two cars are going to appeal to a different sort of buyer.

The i40 is clearly targeted at a more upmarket clientele, given it offers a very Euro chic diesel engine, crisper design and a better stance. Stylistically, the Sonata is all about substance, given its roomier and more logical cabin and cushier ride.

Of course, the fact the Sonata goes like the clappers and the i40 doesn’t clouds this a little.

But to speculate that these differences are enough to stop these cars being cross-shopped would be silly. There’s every chance Hyundai’s sales-people will be directing prospective buyers between the two on a regular basis.

If the driveway test is your main consideration, the i40 takes the win. It’s a genuinely sharp design. Likewise, if fuel savings are a priority, the diesel is to one to go for. It’s also a cheaper ownership proposition, and has more safety equipment.

To counter, the Sonata offers a more spacious and well-presented cabin, a more comfortable ride and an engine that is capable of delivering moments of fun in spades. Personally, I’d have the i40, but against our metrics the Sonata is probably half-a-point better despite the servicing intervals.

Each, though, is a worthy option in a class that also contains price-point rivals such as the excellent Mazda 6, Ford Mondeo and Subaru Liberty.

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