2021 Kia K5 Sedan Review: Former Optima Is Nearly Optimal

Posted on: August 26, 2020, by :


The verdict:
 A stylish redesign that should have left its new name and optional touchscreen system on the drawing board.

Versus the competition: A more attractive take than Hyundai’s frowny new Sonata, the K5 is plenty competitive, but the disparity between its available touchscreen systems is an opportunity missed, and while its powertrain lag might boost gas mileage, it would be wiser to outperform competitors equipped with continuously variable automatic transmissions.

When I reviewed the 2020 Sonata, I was impressed Hyundai hadn’t phoned in its redesign at a time when interest in sedans is waning. Many automakers have ceded the mid-size sedan class to stalwarts like the Honda Accord, Nissan Altima and Toyota Camry — either completely, by bailing out, or passively, by starving their models of resources. Now you can add another brand, though a related one, that hasn’t thrown in the towel: Kia. With a model the company pitches as so different it deserved a new name, the K5 (formerly the Optima) has a lot in common with the new Sonata (which is also quite different yet retains its name). The two cars share a platform, though the Sonata is built in Montgomery, Ala., and the K5 comes together in West Point, Ga.

The K5 has a slightly longer wheelbase than the Sonata (112.2 versus 111.8 inches), and its track is wider, by more than an inch when you compare some trim levels. Currently it comes only with the 180-horsepower, turbocharged 1.6-liter four-cylinder engine that powers the Sonata SEL Plus and Limited trim levels. Though the eight-speed automatic transmission is the same, the K5 has a traditional gear selector lever rather than the Sonata’s push-button controls.

I tested two trim levels: the GT-Line (the red sample in the photos) and an EX (the blue). To understand the K5 lineup, you need to know what’s coming later this year: the K5 GT 2.5T. As the name suggests, it will have a turbocharged 2.5-liter four-cylinder engine that will generate 290 hp — presumably comparable to the coming 2021 Hyundai Sonata N-Line.

Wait, a GT-Line Isn’t a GT 2.5T?

Unfortunately, Hyundai’s use of “N-Line” only confuses things further, as Kia is using a different approach with the word “line.” The K5 GT-Line I tested is the middle of five trim levels, and it’s no GT 2.5T. Where Hyundai uses “N-Line” to designate its performance models, Kia’s use of “line” takes a page from German brands like Audi and BMW, who create sportier-looking trim levels that borrow from their top performance versions but aren’t necessarily more robust. For example, an Audi A5 with the S Line package might look like an Audi S5, but only the latter has the more powerful engine. Ditto for the Kia K5 GT-Line, which definitely looks sportier and has a flat-bottom steering wheel, but is otherwise mechanically identical to the other non-GT 2.5T trim levels. The performance goods will come later this year with the GT 2.5T, currently scheduled for November.

Note that the base, LX, trim is typically stripped down to achieve its starting price of $24,455. It lacks push-button start, an engine immobilizer, a folding backseat and power rear child safety locks, and it’s not eligible for satellite radio. It includes Kia’s basic forward collision warning with automatic emergency braking, but it doesn’t have rear cross-traffic alert with automatic braking or a blind spot collision avoidance system, both of which are standard on all other K5 trims. The LXS adds more standard features and eligibility for some options the LX can’t have, such as heated seats. Then come the GT-Line and EX I tested, of which the EX represents the greater increase in actual content — apart from the styling differences.

2021 Kia K5 GT Line instrument panel with safety tech features
2021 Kia K5 GT-LineCars.com photo by Joe Wiesenfelder

I tested front-wheel-drive versions, but later this year Kia will begin to offer all-wheel drive on the LXS and GT-Line. Asked why AWD wouldn’t be offered on the EX, Kia representatives said it’s not out of the question, but for now the company is following the research, which said the middle of the lineup is where most demand will be.

Hesitate, Accelerate

I had mixed impressions about the powertrain. The engine is fine in some respects; it’s impressive how much power and torque — 195 pounds-feet at 1,500 rpm — a tiny four-cylinder can provide, but with this small displacement and a turbo, some lag is inevitable no matter what technological steps are taken. I started noticing a consistent delay every time I stepped on the accelerator while already in motion, regardless of speed. Truly. Every. Single. Time. Ultimately I determined by watching the tachometer that the transmission would downshift before the car would accelerate, explaining the lag — something I’ve experienced in a couple other cars with small engines and high gear counts over the years. The gear ratios are close enough and the transmission refined enough that you don’t really notice the shift, but you can’t miss the time it takes before the car accelerates.

2021 Kia K5 GT Line engine
2021 Kia K5 GT-LineCars.com photo by Joe Wiesenfelder

Just to check myself, I switched to manual shifting using the gear selector (steering-wheel paddles come only on the GT 2.5T), and sure enough the delay vanished, but I had to choose a lower gear to accelerate appreciably. What’s all this about? Typically it’s the way the drivetrain is tuned for efficiency: The transmission picks the highest possible gear, and even a modest request for acceleration requires a downshift. The K5 has a drive mode selector knob on the console, and I found the Sport and Smart settings both cut back on the delay somewhat by holding onto lower gears in some cases, but of course these modes compromise gas mileage.

Reality check: Though these were both technically preproduction cars, they were pretty late preproduction and nicely buttoned up. Over the decades when we’ve raised concerns like these about transmission behavior, automakers (not necessarily Kia) have typically relied on the preproduction or “learning transmission” defense, which states, conveniently, that modern transmissions adapt to the driving styles of their operators, so it might just take a while for it to adapt (perhaps longer than we’re testing the car?). For the record, zero percent of those other-car transmission complaints magically vanished in later testing, with the exception of one Saturn that was recalled for reprogramming.

Is this delay in the K5 something typical drivers will really notice? I suspect some will and some won’t. The best thing you can do is pay attention to it if you test-drive the K5. Also, know that the K5 GT 2.5T will have a different transmission altogether — an eight-speed dual-clutch versus the current conventional automatic with a torque converter.

2021 Kia K5 GT Line gearshift and cupholders
2021 Kia K5 GT-LineCars.com photo by Joe Wiesenfelder

If the delay I experienced is due to tuning, what does it get you? Tested in the normal drivetrain mode, the EPA-estimated fuel efficiency is 27/37/31 mpg city/highway/combined for most 1.6-liter front-drive trim levels; it’s higher, 29/38/32 mpg, for the LX. (The EPA hasn’t rated all-wheel-drive and GT 2.5T versions yet, but Kia predicts AWD will result in 26/34/29 mpg.)

For comparison, the most efficient 2021 Hyundai Sonata (a lower trim level with a different engine) gets 32 mpg combined, while higher trims powered by the 1.6-liter turbo are rated 30 mpg combined. The 2021 Accord ranges from 26 to 33 mpg combined, the 2020 Nissan Altima ranges from 29 to 32 mpg combined, and the front-drive 2020 Toyota Camry four-cylinder spans 31 to 34 mpg combined.

The K5 faces tough competition on gas mileage, but some of its rivals have continuously variable automatic transmissions, which aren’t anyone’s favorite for drivability. It might have been smarter for Kia to take the hit on mpg here in the land of cheap gas with more responsive transmission programming, and beat the others on drivability as only a well-executed step-gear transmission can.

Ride and Handling

The K5 rides nicely. It’s a reasonable mix of comfort and road feel that’s not trying to be too sporty — it leaves that for the coming GT 2.5T. Both my GT-Line and EX had 18-inch alloy wheels fitted with Pirelli P Zero all-season tires. LX and LXS trim levels come with 16-inch alloys, and the GT 2.5T will have 19s.

2021 Kia K5 GT Line front wheel
2021 Kia K5 EXCars.com photo by Joe Wiesenfelder

Handling is a similar story: competent, but not thrill-inducing. Again, the full GT is likely to be the one to watch for that, because it will have a sport-tuned suspension and its power-assist motor mounted to the steering rack rather than the column, which is generally accepted as a superior placement for feedback and performance.

The GT will also have larger brake discs, front and rear, which seems wise given the additional power. For what it’s worth, though, I found the brake pedal feel in the K5s I drove to be a welcome break from the many by-wire braking systems I’ve encountered lately. It was wonderfully linear and easy to modulate. Is it the conventional vacuum-boosted type? Yep. Did I prefer it? Sure did.

In the Cabin

How you react to the K5’s interior might depend on which one you enter. The GT-Line is so sportified on the outside I was a little let down by the inside. Apart from the flat-bottom steering wheel and identified seats, not much is special about it; it looks like a mid-level cabin — which, of course, it is. Entering from the LXS’ more modest exterior, or finding the more lush interior of an EX, might not evoke the same disappointment.

That’s not to say it’s bad. The materials are pretty nice, and the GT-Line had the smaller 8-inch touchscreen, which, as I explain below, is actually superior. The K5 doesn’t offer leather upholstery. The two lowest trim levels have manual cloth seats, the GT-Line adds a power driver’s seat and mixes cloth with leatherette (imitation leather), and the EX and GT 2.5T go full leatherette, though with separate designs. The front passenger seat has a standard height adjustment, which is nice to have (and no guarantee in today’s market). Power adjustment is optional on the EX and GT 2.5T.

I found the driver’s seat to be comfortable, with exceptional seat travel — always nice for long-legged drivers. At 6-feet tall I didn’t even sit all the way back. When I raised the seat all the way, my head (not just my hair) contacted the roof alongside the panoramic moonroof, which is optional on the GT-Line and standard on the two highest trims.

The backseat’s outboard positions are also roomy and comfortable. I had about an inch of headroom to spare, and my knees were raised only a little bit by the height of the floor — an improvement over the Sonata. The center position, however, wasn’t usable by someone of my height, as my head was pushing into the ceiling. (I’ve found adequate headroom in many center rear seats, including in smaller size classes.) By the numbers, the K5’s backseat legroom is better than the Sonata’s by almost a half-inch, and it feels like it, but the Accord and Camry are both several inches roomier (see the specs side by side). The specs also show the Kia shy of backseat headroom versus the Sonata and Camry, but the Accord is listed as having 0.2 inch less.

2021 Kia K5 GT Line center stack display screen and GPS navigation
2021 Kia K5 GT-LineCars.com photo by Joe Wiesenfelder

Usability and Those Touchscreens

Boil it down and usability includes everything from conventional controls to what’s often minimized as the “multimedia system.” Overall, Kias can be as no-nonsense as any vehicle, depending on your perspective. A lot of folks think push-button transmissions are nonsense, so chalk one up for Kia, which uses a standard lever. Similarly, the K5’s standard issue controls are all mechanical push buttons, switches and knobs rather than touch-sensitive capacitive panels (aka, cost-saving nonsense). Drive modes can be changed via a rotary knob on the center console that you don’t have to look for — or at — in order to operate. All good.

2021 Kia K5 GT Line center stack display screen and GPS navigation
2021 Kia K5 EX with Premium PackageCars.com photo by Joe Wiesenfelder

Remote controllers with separate displays are often nonsense, but Kia went with a standard 8-inch touchscreen supported by a volume knob, a tuning knob and more mechanical buttons, along with one of the first standard wireless applications of Apple CarPlay and Android Auto. Great, right? Right. My EX, however, was equipped with the optional 10.25-inch touchscreen system. In the words of Hannibal Lecter, “No no no, you were doing fine … ”

2021 Kia K5 GT Line center stack display screen with Android Auto
2021 Kia K5 EX with Premium Package and wired Android AutoCars.com photo by Joe Wiesenfelder

Right off the bat, this system eliminates the tuning knob, which bothers some people. It trades real buttons for capacitive ones, which bothers us. It sacrifices wireless CarPlay and Android Auto, reverting to the wired versions, for a screen that’s larger — or is it? Screens are measured diagonally, and if you bother to measure for yourself, as I did, you’ll find that the standard screen is 7 inches wide by 4 inches high. The optional screen’s image area is 9.5 inches wide but only 3.6 inches high. If you pay any attention to such things, you realize that display height is more important than width in many important areas, including mapping, backup camera views and definitely Android Auto, which gets only the left two-thirds of this screen rather than the whole one in the standard system. Android Auto users will probably conclude that this “upgrade” is actually a net loss.

2021 Kia K5 GT Line center stack display screen with Android Auto
2021 Kia K5 GT-Line with standard touchscreen and wireless Android AutoCars.com photo by Joe Wiesenfelder

In fairness, though, wireless Android Auto is no bargain, in my opinion. You’re spared the unfathomable inconvenience of plugging a cord into your phone, but AA puts your phone to work, and you’re likely to leave the car with less battery life than you started out with if you don’t plug it in. I used the K5 EX’s wireless charging pad, and it still slowly lost its state of charge while my Samsung Galaxy S10 routed me and played SiriusXM. Even powerful wireless charging pads typically result in slower charging than the cord method, as we recently illustrated. (Kia’s claims of increased charging rates and a dedicated cooling fan both fell flat.) The same scenario when instead plugged into one of the K5 EX’s USB charging ports did increase the phone’s state of charge, though not by much. If you’re going to plug in anyway, you can live without a wireless smartphone interface.

2021 Kia K5 GT Line wireless smartphone charging station
2021 Kia K5 GT-LineCars.com photo by Joe Wiesenfelder

There’s plenty wrong with the K5’s touchscreen “upgrade,” but the loss of wireless CarPlay and Android Auto isn’t it — it’s everything else detailed above. I should mention that the system also adds proprietary voice control, but I’ve never been one to control machines via voice, so I struggle to see the value. Your results may vary. Unfortunately, this feature isn’t a stand-alone option but rather part of the Premium Package ($3,400). If you want to avoid the touchscreen “upgrade” and stick with the 8-inch touchscreen, you’ll have to forgo Bose premium audio, a power front passenger seat, memory driver’s seat and outside mirrors, a heated steering wheel, the excellent Highway Driving Assist, Safe Exit Assist, rear parking collision avoidance and more.

Without the Premium Package you’ll also miss out on Active Sound Design, which augments the engine sound through the stereo, ironically making my tamer-looking K5 EX sound sportier than the sporty-looking GT-Line. What it didn’t do, however, was sound at all different when I changed the selectable settings. Kia later explained the differences are greatest under heavy load and high rpm (not my driving circumstances), and that the effect will be stronger in the GT 2.5T.

2021 Kia K5 GT Line center stack display screen
2021 Kia K5 EX with Premium PackageCars.com photo by Joe Wiesenfelder

Should You Buy a Kia K5?

Even if you skip the stripped LX trim level, the K5 is nicely equipped for the price, coming in at $25,455 for the LXS, $26,355 for the GT-Line and $28,955 for the EX, including destination charges. Once available, AWD will add $2,100 to the LXS and $3,700 to the GT-Line. These prices seem a bit steep considering Toyota’s AWD is $1,400 across the board, but the price increase includes features beyond AWD. For example, the LXS also adds heated seats and telematics to enable remote engine start, presuming the car will be used in cold climates. The GT-Line with AWD includes the Premium Package, which would be a $1,600 option with FWD. Kia’s warranty remains tops with five-year/60,000-mile bumper-to-bumper and roadside assistance coverage and a 10-year/100,000-mile powertrain plan.