The 2012 Chevrolet Sonic debuted at the North American International Auto Show as the first B-segment passenger car to be assembled in the U.S. It launches later this year at General Motors’ retooled Orion, MI, assembly plant.
A replacement for the Aveo, the new Sonic aims to make small cars profitable for GM by offering high levels of feature content, a fresh exterior form, and spritely performance and efficiency. It rides on GM’s Global Gamma architecture and fits into the automaker’s portfolio between Chevy's Spark (Global Mini platform) and C-segment Cruze (Delta II).
GM Europe and GM-Daewoo in Korea shared in the development of the front-drive Sonic’s platform. The car will be offered in four-door sedan and five-door hatchback body styles. Competitive targets are the Ford Fiesta, Honda Fit, and Toyota Yaris.
The five-door model intentionally resembles a three-door hatch, because its rear door handles are discreetly located in the C-pillar area.
Compared with Cruze, the Sonic sedan is 11 in (279 mm) shorter overall and 2 in (51 mm) narrower, and it has a 6-in (152-mm) shorter wheelbase. It is also 500 lb (227 kg) lighter.
One of the engineering team’s primary goals was to create one of the stiffest body shells in the global B segment, according to veteran GM Engineering Executive Director Jim Federico. The sedan’s body-in-white measures 28 Hz in first-bending and torsional performance, he told AEI.
The team “pushed the limits of high-strength steel use on this program,” Federico added.
The structural rigidity enabled engineers to tune the ride and handling more precisely. Engineers from the Corvette program were involved in development and calibration. Sonic’s flat-top-frame cradle is a unique design that Federico said optimizes stiffness in the front chassis portion of the vehicle.
Sonic’s front suspension comprises MacPherson struts with coil springs and stabilizer bar. The struts include side-load compensator springs for lower noise operation, Federico said. In the rear, a semi-independent, compound-link-type suspension uses a tubular V-profile torsion beam with gas-charged shocks. Essentially a straight axle without contour, the rear beam-type design optimizes packaging and is claimed to reduce road-induced NVH.
Front and rear tracks are identical at 59.4 in (1509 mm). Wheelbase is 99.4 in (2525 mm). Overall length of the sedan is 173.1 in (4399 mm); the hatchback is 159 in (4039 mm) long. Overall width for both models is 68.3 in (1735 mm), and overall height is 59.7 in (1517 mm). Curb weights have not yet been released.
EPA passenger volume for the Sonic sedan is 90.4 ft³ (2560 L) and 90.6 ft³ (2565 L) for the five-door model.
Sonic’s electric power steering (EPS) features a patented wear compensator that Federico said ensures life-of-the-vehicle steering precision by continually adjusting the system interaction with the steering gear. The foundation brakes are front disc/rear drum with four-channel ABS and brake-force distribution. The front rotors are 10.8-in (276-mm) diameter; rear drums measure 9 in (230 mm).
The chassis control package features StabiliTrak ESC with rollover sensor. Road wheel sizes range up to 17 in. GM engineers claim a 34.5-ft (10.5-m) curb-to-curb turning circle with 14-, 15-, and 16-in wheels, and a 36.1-ft (11-m) circle with the 17’s.
Sonic’s available powertrain for North America matches that of the Cruze. Standard will be the naturally aspirated 1.8-L Ecotec gasoline four-cylinder, its preliminary output of 135 hp (101 kW) and 123 lb·ft (167 N·m) at 3800 rpm. Engineers claim approximately 90% of peak torque will be available from 2400 to 6500 rpm.
Optional will be the turbocharged 1.4 L Family Zero Ecotec estimated at 138 hp (103 kW) and 148 lb·ft (200 N·m) available between 1850-4900 rpm. Both engines are port-injected.
Three transmissions are available: an M26 five-speed manual and 6T30 six-speed automatic with the 1.8 L, and an M32 six-speed manual with the 1.4-L turbo. Final drive ratios are 3.94:, 3.47:, and 3.65:1 with the respective transmissions.
The car’s fuel tank capacity is 12.1 gal (45.8 L).
Sonic’s telematics suite includes OnStar with six months of turn-by-turn navigation. Available features include XM Satellite Radio, USB, Bluetooth, and MyChevrolet mobile application with OnStar MyLink vehicle connectivity.