2018 Kia Optima vs Mazda 6

What's the difference?

If you travel long distances, want a good amount of space and don’t want to pay big bucks for a new car, then yeah, maybe there is a reason sedans like this will hang around for a while longer.

Sure, the appeal of sedans mightn’t be as strong as it once was, but models like the Kia Optima prove they still have a reason to exist.

The Mazda 6's competition is not nearly as good looking, and none have that smooth 2.5-litre turbo to get them whistling along with such little fuss.

You can buy a Camry and enjoy the solid drive, or a Kia Optima and enjoy the, erm, exclusivity. Or the turbo Hyundai Sonata, which is also somewhat exclusive.

The GT is a terrific car, and it's terrific because of its smooth, powerful and calming engine. It's a shame that the engine is only available in the top end of the range, though...

Cosmetic changes for the facelifted 2018 Kia Optima include new headlights and tail-lights with revised LED signatures (but still halogen lamps in the base model), and there are newly sculpted bumpers and new wheel designs across the two-model range. 

We had the base model Si, which doesn’t look as good as the GT model, because it has smaller wheels, the sporty body kit and misses out on the LED headlights, but the LED daytime running lights are still present.

The GT has a more aggressive look, and the side skirts, front spoiler and rear diffuser fit it better - there are dual exhausts, but not sporty quad exhaust tips.

In fact, this model is a bit like the old-man version of the Optima. No offence intended to old men, of course. The GT is just heaps sportier, and I reckon it’s considerably more attractive as a result. 

Still, the inherent sleek styling of the Optima remains - the chrome highlighting along the window line is a bit too sheeny for me, but the angles and stance of this model are quite gracious. I really dig the fact the top of the windscreen mirrors the ‘Tiger Nose’ grille shape.

I'm no exterior designer, but I liked the existing Optima more - it just looked a bit neater, even though it had a decent amount of bling with its Mercedes-like diamond-pattern grille, as opposed to the cheese grater look seen here.

There’s not quite as much bling inside the cabin of the Si, either, but it is still a well-designed space - just not as special as the premium package offering of the GT (which gets leather trim - not nappa leather, but still a quality cowhide finish, and more). Check out our interior photos to see if you agree - but size and interior dimensions of the Optima are hard to argue against.

The 6 is a seriously good-looking car, and I mean that in a head-turning, wolf-whistling kind of way.

Mazda's Kodo design language rarely disappoints. Here in the 6, the facelift is similar in nature to the CX-5 - slimmed headlights, simplified shapes front and rear, but a muscular, lithe profile.

Changes in the cabin have been more noticeable, because unlike the exterior design, Things Needed To Happen. The old interior wasn't bad, but Mazda had this terrible habit of making its cabins dark and gloomy.

A simple thing like sending some of the indicator lights up into a unit with the rear vision mirror significantly reduced the clutter on the centre console. There's a distinct Audi influence in the way the horizontal stacked sections make the cabin feel wider and more airy, too. Just about everything has been changed, except the steering wheel and the shifter, and it's worked.

I really like the way Kia designs its cabins. Sure, there’s a lot of black in here, but there’s also a lot of thought put into the usability of the space.  

The high-mounted 7.0-inch infotainment and multimedia touch screen in the Si is simple to use, and for 2018 the Optima range gets Apple CarPlay and Android Auto - you couldn’t get that in the Optima up to this point. 

Also included are a reversing camera, USB input, Bluetooth phone and audio streaming and six speakers. The Si model misses out on sat nav - you’ll have to use the maps app on your phone. No DVD player either.

Storage is well thought out in here, with big bottle holders in the doors, a good sized pair of cup holders up front, and a nice little storage bin for your phone, wallet, keys and so on.

There’s a driver info screen with a digital speedo, and even on this base model you get a dual-zone climate control air conditioner. The updated Optima gets a new steering wheel, too.

Now, what about the back seat?

It may be considered a ‘mid-sized’ sedan, but there’s limo-like space. With the driver’s seat in my position (I’m about six feet tall) there was still heaps of rear legroom in the rear seat, with ample knee room, good foot room and decent shoulder space, too - three of me could slot across the back bench comfortably, which means kids will fit easily, too. There are three top-tether points and two ISOFIX points as well.

Kids and adults alike will be happy with the rear air vents back here, and there’s a flip down armrest with cupholders, too. Again, big bottle holders appear in the doors, and there are map pockets in the back seats.

What about boot space? With so many people choosing SUVs over sedans because they’re theoretically more practical, the Optima offers good food for thought - it has enough luggage capacity for a bunch of suitcases (510 litres VDA in size) and there’s a full-size alloy spare under the boot floor. If you need more, you could always invest in a roof rack setup?

Front-seat passengers score a pair of cupholders with a neat cover for when they're not in use. The centre console is on the smaller side, but a decent phone cubby under the climate controls makes up for that. The fold-down centre armrest features a pair of cupholders, too, plus there's a slot to hold a phone or small tablet upright, and a small lidded tray with a pair of USB ports.

There is plenty of room for front-seat passengers, and even those in the rear won't run into any headroom trouble. There is plenty of leg room, too, as well as decent foot room. Smaller folks will be okay in the middle seat.

Boot space isn't too bad, at 474 litres (VDA) with the rear seats in place.

The GT is third in a four-model line-up that starts with the $32,940 Sport and ends with the $50,090 Atenza diesel. The GT is the first in the range to feature the turbocharged petrol engine, which is kind of sad, because a turbo-powered Sport would be brilliant.

Starting at $43,990, you get 19-inch alloys, active LED headlights, black or white leather seats, power heated and folding mirrors, power windows, electric seats, an 11-speaker Bose stereo, auto headlights and wipers, dual-zone climate control, leather steering wheel and shifter, sat nav, keyless entry and start, active cruise control, adaptive headlights, front and rear parking sensors, heated front and rear seats and a space-saver spare.

Mazda's 'MZD Connect' multimedia system is accessible through the dash-mounted touchscreen and a console-mounted rotary dial. And my usual whinge about the lack of Apple CarPlay and Android Auto now has a happy-ish ending - by the end of 2018, you'll be able to retrofit both. Not perfect, but even older Mazdas dating back to 2014 are upgradeable.

The Si model is powered by a 2.4-litre four-cylinder petrol engine, which has seen no changes to its specifications for this mid-life update.

Engine specs remain at 138kW of power at 6000rpm, while torque is rated at 241Nm at 4000rpm. It makes use of a six-speed automatic transmission only - there’s no manual transmission here, but you do get paddle shifters - and it's front wheel drive (the Optima isn't available with AWD, or as a 4x4, or in rear wheel drive - the latter is left to its bigger brother, the Stinger).

The GT gets a zestier drivetrain with more horsepower - it has a 2.0-litre turbo four-cylinder engine with 180kW/350Nm, which is much more desirable, but also louder than the Si’s 2.4. It also has a six-speed auto transmission, and is FWD. If you're into ratings and statistics, that 2.0-litre with a turbocharger is one of the perkier offerings for its engine size in the class.

There is no hybrid model available, despite a plug in hybrid petrol version (allowing you to run in EV mode) being sold in European markets. No diesel here, either, while other markets get a 1.7-litre turbo diesel. No LPG model here, or anywhere else, for that matter.

Towing capacity for Optima models is 750kg unbraked and 1700kg braked for the 2.4-litre, and 700kg/1400kg for the 2.0-litre turbo. Tow bar down-weight is capped at 80kg.

If you're concerned about engine problems, suspension problems, clutch and transmission issues, be sure to check out our Kia Optima problems page.

Mazda slaps a 'SkyActiv' badge on just about everything, so it will be no surprise to find that this engine bears the name. The GT's 2.5-litre four cylinder spins up 170kW and 420Nm - the same figure as the CX-9, but with a quite a few less kilos to haul.

The 6 is front-wheel drive, and power reaches those wheels via a six-speed automatic. I didn't think a six-speed 'box would be enough, but it didn't bother me at all.

Towing capacity is rated at 550kg unbraked and 1550kg braked.

Kia claims a very realistic fuel economy rating of 8.3 litres per 100 kilometres for the Si model, and we saw damn close to that consumption during our week of testing. On the highway it will sit at around 6.5L/100km, ensuring good mileage, while city driving will push usage above 12.0L/100km. Our overall average was 8.5L/100km, which is good. Use the eco mode, and you'll get a little better use.

The turbocharged GT model uses a little more, according to Kia’s 8.5L/100km combined average claim, but we guarantee you’ll actually use more than that because it’s more eager to please.

Fuel tank capacity is 70 litres - plenty of size for long distance drives.

Mazda says that the 2.5-litre turbo drinks 91RON (yep, the cheaper stuff) at the rate of 7.5L/100km.

My week with the car in mostly urban driving yielded a disappointing 11.3L/100km. That might have had something to do with my right foot, but that's classified information.

The Optima has some really good elements to the way it drives, but sadly  some less impressive bits as well.

Let’s start with the not-so-great stuff - the 2.4-litre engine in this Si model just isn’t as enjoyable as the turbo unit, and the fact that Kia still doesn’t offer a hybrid version here, despite doing so elsewhere, is a bit of a downer.

The drivetrain isn’t terrible - the six-speed auto is smart enough, and there’s usable power if you boot it. The two more sedate drive modes, 'Eco' and 'Comfort', mean the transmission will aim to save fuel and limit throttle response, with a bit more of a lazy feel to the drive experience. But in 'Sport' mode it is definitely more rewarding in terms of acceleration and performance, offering a bit more pep and urgency (we didn't do a 0-100 km/h speed test, but take our word for it); it undoubtedly at the cost of fuel consumption.

It’s just a bit of a shame Kia doesn’t offer the turbo in this spec, too. Fuel use for the Si model is better than the turbo, however, so it could be ideal for buyers who are more worried about the bottom line than design and a sportier drive.

The thing I like most about the Optima is its road manners - the steering and suspension have been tuned for local conditions, just like all Kia products, and it shows. 

The electric power steering is really well sorted, making for easy parking moves and good assuredness at higher speeds. And the turning circle is decent, too - 10.9m (so, the turning radius is 5.45m). 

Plus the ride comfort is really good. On the highway it coasts along with very little fuss, and around town it deals with lumps and bumps impressively. Sharp edges can upset things a tad, and mid-corner bumps can make it jitterbug a little bit, but not to a degree that would rule it out of contention if you want a mid-sized sedan.

It’s pretty quiet on the open road, too, and the adaptive cruise control makes long-distance driving a simple task. The GT does suffer a little bit more road noise, though.

Okay, I feel I've misled you a little, way back at the beginning of this story.

I feel like I may have intimated that shoving this turbocharged engine under the bonnet meant a transformation to something a bit hotter. After all, it has a lot more torque than the fondly remembered 6 MPS, and isn't all that short of that monster's power figure either.

It's nowhere near a replacement for the 6 MPS, though. In fact, it's better than that.

Mazda got out of performance cars a long time ago, preferring to just pretend there's another RX-7 on the way (that story always surfaces in April for some reason). The new turbo engine isn't a huffing, puffing performer. It's actually borderline dull. It isn't peaky or laggy, but super-quiet and super smooth.

You can surf along on the torque, overtake with far less planning and buttock-clenching.

Adding the turbo engine to the 6 fixes what was an extremely competent car looking for a good engine. The standard petrol in the lower-spec cars is adequate, but it's not really up to the task of swift, effortless progress.

This turbocharged unit actually calms the driving experience because you know you can surf along on the torque, overtake with far less planning and buttock-clenching.

The rest of the car? Well it's as lovely and easygoing as ever. The new car is stiffer than before, and, like most Mazda updates, is filled with detail changes that add up to a significant improvement.

It's so much quieter, too, with just a bit of racket from the GT's bigger wheels over coarse surfaces. Most of the suspension noise from the older cars is gone.

Passengers really liked the interior of the 6, with its broader, airier feel, and in Soul Red with the white interior, it looks properly classy.

The 6 arrives with six airbags, ABS, stability and traction controls, high beam control, lane-departure warning, lane-keep assist, blind-spot monitoring, forward and reverse AEB, reverse cross-traffic alert, a reversing camera and traffic-sign recognition.

ANCAP awarded the Mazda a maximum five stars in 2012.

Kia remains a shining light in terms of its new-car-ownership promise, with a very strong seven-year/unlimited kilometre warranty. It makes a lot of sense if you plan to hang onto the car for a while. There's no extended warranty available, which is understandable.

That plan also includes a roadside-assist plan for the same seven-year period, provided you maintain your car with Kia Australia. So, given you get one year to start with, then you get an extra year of cover every time you go back to Kia to get your car serviced, you could end up with eight years of coverage. Nice!

Servicing is due every 12 months or 15,000km, with the first seven years covered by a capped-price-service cost / maintenance cost plan. The costs are: service one - $289; two - $466; three - $360; four - $559; five - $325; six - $599; seven - $345. That makes a total cost of $2943, which is competitive for its class. Keep your owners manual or logbook up to date, and your resale value should hold up better.

If you have concerns about common problems, issues, reliability ratings and durability, you should check out our Kia Optima problems page.

Mazda recently increased its long-standing three-year warranty to five years/unlimited kilometres, which was odd, because at the car's launch in May, they said three years was plenty. Still, I'm not arguing with the change.

Roadside assist, sadly, is not part of the deal. It costs between $99 and $109 per year.

Service intervals are a bit close at 12 months or 10,000km, whichever comes first. Prices are capped for the first five years, alternating between $312 and $341 for a total of $1618 for the first 50,000km.