For instance, a more upscale Impala is in the works, with a low production volume and limited rental fleet sales, one source says. That would follow the example set by the 2010 Ford Taurus. But the new Impala is not coming until the 2014 model year.

In the nearer term, Chevrolet will prepare for rising federal fuel economy standards by decreasing the displacement of its V-6 engines, adding more four-cylinder engines and introducing redesigned small cars.

Here are Chevrolet's 2011-13 model year highlights:

Spark: This minicar will enter the United States as a 2013 model with three- and four-cylinder engines. General Motors Co. is expected to build the first Sparks for this market in South Korea, home of the Spark's sibling, the five-door Daewoo Matiz hatchback. Spark production may move to Mexico later.

The Spark already is on sale in Europe, South Africa and other markets. Expect midcycle updates in time for the U.S. model's debut.

Aveo: GM will start producing the redesigned subcompact in mid-2011 at Orion Township, Mich. The car will be longer and wider than the current Aveo and have a five-door hatchback and four-door sedan. Production is expected to reach 60,000 to 70,000 annually.

Cruze: The 2011 Cruze will reach U.S. showrooms in September, replacing the Cobalt. The four-door compact car went on sale in Europe and Asia last year.

HHR: GM will discontinue this retro-styled wagon at the end of the 2011 model year.

Volt: The plug-in hybrid launches in October or November. Sales will start in New York City, Michigan, California, Washington and Austin, Texas, and then expand to all 50 states within 12 to 18 months. GM has said it will build 10,000 Volts by the end of 2011 and 45,000 in 2012.

Malibu: The restyled, re-engineered Malibu will debut in 2012 as a 2013 model. It will have the new, direct-injection, four-cylinder engine promised to GM's plant in Tonawanda, N.Y. The sedan will lose 4 inches off its wheelbase and have a larger trunk, because it's moving from the longer version of GM's Epsilon platform to the shorter version.

Camaro: The Camaro convertible arrives early next year, likely as a 2012 model. A Camaro redesign is planned for the 2015 model year, switching the car from its current Zeta platform to the smaller Alpha platform.

Impala: The upcoming redesign, timed for the 2014 model year, will move this full-sized car to the longer version of the Epsilon platform, which the current Buick LaCrosse uses. The Impala's current platform dates back to the mid-1990s. The 2014 Impala will have shorter front and rear overhangs to save weight and fuel and will feel roomier inside. A four-cylinder engine will come standard, with an optional six-cylinder and possibly a hybrid.

Corvette: GM would like to launch the redesigned Corvette in the 2013 model year, timed with the sports car's 60th anniversary. But introducing the car so soon is a stretch, so the new version is more likely to come in the 2014 model year. A turbocharged V6 may join GM's next-generation V8s on the next version of the Corvette. The company is working on a twin-turbocharged V6 that could show up here.

Compact crossover: Chevrolet is considering a five-seat compact crossover smaller than the Equinox for the 2013 model year.

Equinox: The Equinox will get a freshening in the 2013 model year. It also may receive a hybrid version around the 2014 model year.

Traverse: This crossover gets a freshening in the 2013 model year, along with a 3.0-liter V6 engine instead of its current 3.6-liter version.

Tahoe, Suburban: GM was looking at putting the Tahoe on the Lambda crossover platform. But now GM will keep the Tahoe and Suburban SUVs on the next-generation large-truck platform. The redesigned Tahoe and Suburban will appear in the 2014 model year, and they probably will share more front-end sheet metal with the Silverado pickup to cut costs.

Avalanche: GM probably will kill the pickup by the 2013 model year.

Colorado: GM will idle its plant in Shreveport, La., by June 2012, discontinuing the Colorado. A decision to reintroduce a compact pickup could come a couple of years later. GM will sell a next-generation global Colorado outside the United States. That vehicle could come here. But GM is leaning toward an even smaller design, such as a version of Brazil's Chevrolet Montana. Whatever the decision, GM will have to decide whether to assemble the pickup in the United States or use cheaper labor elsewhere and pay the 25 percent "chicken tax" on imported pickups.

Silverado 1500: A natural-gas-powered version probably will appear in 2012. The pickup will be re-engineered and restyled for the 2014 model year.

Silverado 2500, 3500: GM re-engineered its heavy-duty pickups for the 2011 model year. A restyle is expected in the 2014 or 2015 model year. These pickups also will get compressed-natural-gas versions in about two years.

Express: The van gets natural-gas capability in the 2011 model year.