A new engine joins the 2015 Hyundai Sonata lineup, on top of the existing 2.4-liter four-cylinder, 2.0-liter turbo, and hybrid powertrains. Hyundai’s Gamma 1.6-liter turbocharged I-4 pairs with a new seven-speed dual-clutch transmission for more than ten percent better fuel economy than the base 2.4-liter engine offers with its six-speed automatic.
By comparison, the standard 2.4-liter 2015 Hyundai Sonata has marginally higher horsepower but noticeably less torque—185 hp and 178 lb-ft. Fuel economy for the Eco model is estimated at 28/38/32 mpg (city/highway/combined), which improves significantly on the 2.4-liter Sonata’s 25/37/29 mpg ratings and puts it right near the top of the midsize segment for combined ratings. Particularly in the city, the 2015 Hyundai Sonata Eco will edge out its naturally-aspirated sibling’s mileage, ideally without feeling strained thanks to its low-end torque curve.
Part of this formula for elevated efficiency is an all-new seven-speed dual-clutch transmission. It’s the first seven-speed dual-clutch for Hyundai, although there is a six-speed dual-clutch transmission in the base, naturally-aspirated 2014 Hyundai Veloster. The 1.6-liter turbocharged Gamma I-4 in the 2015 Hyundai Sonata Eco is related to that used in the Hyundai Veloster Turbo, where it makes 201 hp and 195 lb-ft of torque.
No additional body upgrades were required to achieve the improved fuel economy—the 2015 Hyundai Sonata was already optimized for aerodynamics with a low 0.27 drag coefficient. The Sonata Sport, it turns out, actually loses aero efficiency by trying to look sporty with a bolder body kit, so the Eco uses the standard Sonata as a foundation.
Other than the engine and transmission changes, differentiation between the 2015 Hyundai Sonata Eco and the regular Sonata is minimal. Compared to the Sonata SE, the Eco model gains a chrome grille, turn signals mounted on the side mirrors, automatic headlights, a lumbar-equipped power driver’s seat, chrome trim, Hyundai’s Blue Link infotainment system, and a rear-view backup camera.
The only available package for the 2015 Hyundai Sonata Eco is a $4100 Technology Package. It adds key features like blind-spot monitoring, keyless entry with push-button start, leather interior, heated front seats, navigation, premium audio, satellite radio, and an auto-dimming rear-view mirror.
The 2015 Hyundai Sonata Eco will begin production at Hyundai’s Alabama plant in August, with a starting price of $24,085 including destination fees — $2025 more than the base price of a Sonata SE. The Eco model should go on sale in September.