Posted on October 19, 2023
Don’t get hung up by the new nameplate on the redesigned 2021 Kia K5. This is very much the shapely mid-size sedan formally known as the Kia Optima. We’re a little sad to see a perfectly good vehicle name fall to alphanumeric nonsense, but the Optima has been known as the K5 in the Korean market for more than a decade. The badge on the trunklid takes nothing away from its family sedan goodness. Like its predecessor, it upholds Kia’s increasingly impressive ability to balance upscale execution, design, and value.
At the center of the Optima-to-K5 metamorphosis is the latter’s adoption of the Hyundai-Kia conglomerate’s latest N3 platform, which also underpins the similarly fresh 2020 Hyundai Sonata. We had a brief drive of the new K5 last year around Kia’s home market of South Korea. Compared to the outgoing Optima, the new sedan is 2.0 inches longer, 1.0 inch wider, and 0.8 inch lower. Its 112.2-inch wheelbase also is up 1.8 inches, with that growth primarily going to expanding rear-seat space. Even with the K5’s sloping roofline, six-footers can easily sit behind six-footers.
The Optima was always a looker, and the K5 arguably is even more so with its strong character lines, balanced proportions, and intricate detailing. We’ll leave it to you to decide if the K5’s sharper lines, zigzag LED running lights, and “sharkskin-inspired” grille treatment work better than the Sonata’s demurer look, but there’s no denying this Kia pushes style and design further than what’s expected of the segment.
Driving the Change
Things are comparably tame under the K5’s hood, although the GT model will address that when it arrives later this year with a 290-hp turbocharged 2.5-liter inline-four and an eight-speed dual-clutch automatic transmission. The front-wheel-drive GT-Line and EX models that we drove in Michigan featured the standard 1.6-liter turbo-four—180 horsepower and 195 pound-feet of torque—mated to a conventional, smooth-shifting eight-speed automatic. In our testing of a similar 2020 Sonata, this setup was good for a zero-to-60-mph run in 7.3 seconds. That car also returned 36 mpg on our 75-mph highway fuel-economy test, although some competitors such as the Toyota Camry can top 40 mpg in that measure. For the K5, its EPA estimates top out at 29 mpg city, 38 mpg highway, and 32 mpg combined.
The K5 breaks from the front-drive-only Sonata by offering all-wheel drive. That system will be available later this year as an option only on the volume LXS and GT-Line trim levels. The upgrade won’t come cheap, though. Bundled with a host of otherwise optional equipment, all-wheel drive will add $2100 to the price of the LXS and $3700 to the GT-Line.
Kia says the K5 was tuned separately from the Sonata, yet both share a similar characteristics on the road. The K5’s steering is precise but numb in feel, there’s an initial softness to its brake pedal that firms up when you stand on it, and it goes around corners with reassuring competence and stability. The relatively soft suspension returns good overall ride comfort and moderate body roll in corners, but we would like more insulation from the road. Both of the cars we drove rolled on 18-inch Pirelli P Zero All-Season tires (16s are standard on lesser trims) that provided reasonable levels of grip. Yet, despite a standard acoustically laminated windshield and increased sound-deadening material, road noise is prominent on most surfaces and the big wheels thwack loudly over bumps and pavement seams.
The K5’s 1.6-liter is content with being worked lightly, doling out its peak torque at just 1500 rpm with a subdued thrum. Sport mode energizes things a touch by prompting the eight-speed to hold on to lower gears longer and pumping slightly more engine noise into the interior through the stereo speakers. It also firms up the steering effort a little, albeit with no change to its tactility. But only the K5’s GT model gets paddle shifters, and the standard transmission will upshift on its own well before the engine’s 6500-rpm redline, even with the shift lever slotted into its manual mode.
Kia has significantly upped the Optima’s interior game with excellent fit and finish and a thoughtful sprinkling of not-too-shiny bits. The K5 succeeds in incorporating various styling elements from both Kia’s sportier Stinger hatchback and the Telluride SUV, along with exemplary functionality and ease of use. GT-Line models can be optioned with jazzy red leatherette upholstery with GT-Line logos emblazoned on the front headrests, but we preferred the cooler ambiance of the more luxurious EX model with its greater feature count and its convincing fake-wood detailing. While we would’ve liked to lower the front seats even more in their tracks, the K5’s thrones don’t feel perched as excessively high as the latest Sonata’s.
There are some budget-minded elements to be found, including hard plastics on the door panels, center console, and lower dash. EX models add more soft-touch points and a few niceties that we wish were standard across the range, such as rear climate-control vents. But all K5s come with dual-zone automatic climate control, a crisp (albeit small) 4.2-inch instrument cluster display, and an 8.0-inch center touchscreen. A 10.3-inch touchscreen is optional. Wireless Android Auto and Apple CarPlay connectivity are standard, but strangely, you’ll have to use a power cord to sync with the larger 10.3-inch touchscreen. Kia says it may address that discrepancy with wireless connectivity in a future technical update. Other tech highlights include an optional 12-speaker Bose stereo and wireless device charging.
Even the K5’s competitively priced $24,455 LX base model comes with loads of standard safety gear and driver aids, including forward-collision avoidance with pedestrian detection, automatic high beams, a driver-attention monitor, and lane-keeping assist. Moving up through the lineup unlocks additional assistants, such as navigation-supported adaptive cruise control with stop-and-go capability, rear cross-traffic detection, and blind-spot monitoring. Fully loaded, the front-drive Kia K5 GT-Line costs about $28K, while the more indulgent EX tops out around $32K. That’s slightly less than a new Sonata Limited yet a bit more than you’ll pay for a similarly equipped Honda Accord or Toyota Camry.
The new Kia K5 may not be as engaging to drive as the Accord, which remains our top pick in the segment. And had it been around for our most recent comparison test of family sedans, it probably wouldn’t have improved upon the Sonata’s second-place finish. To be sure, we will let the Kia and the Honda duke it out soon enough. But what the K5 does offer is an impressively styled and smartly executed package that’s studded with features and technology. Optima still has a better ring to it than K5, but Kia’s redesigned mid-sizer is good enough that we don’t really care what it’s called.
2021 Kia K5
front-engine, front- or all-wheel-drive, 5-passenger, 4-door sedan
LX, $24,455; LXS, $25,455; GT-Line, $26,355; EX, $28,955; GT, $31,455
turbocharged and intercooled DOHC 16-valve 1.6-liter inline-4, 180 hp, 195 lb-ft; turbocharged and intercooled DOHC 16-valve 2.5-liter inline-4, 290 hp, 311 lb-ft
8-speed dual-clutch automatic, 8-speed automatic
Wheelbase: 112.2 in
Length: 193.1 in
Width: 73.2 in
Height: 56.9 in
Passenger volume: 102–105 ft3
Trunk volume: 16 ft3
Curb weight (C/D est): 3100–3400 lb
PERFORMANCE (C/D EST)
60 mph: 5.2–7.4 sec
100 mph: 17.8–20.1 sec
1/4 mile: 13.5–15.7 sec
Top speed: 135 mph
EPA FUEL ECONOMY (C/D EST)
Combined/city/highway: 29–32/26–29/35–38 mpg