Wagoner said the GM board has approved production of a new small Chevrolet car at a plant in Lordstown, Ohio, in mid-2010 and production of the Chevrolet Volt electric vehicle in Detroit.
Wagoner announced the moves in response to slumping sales of pickups and SUVs brought on by high oil prices. He said a market shift to smaller vehicles is permanent.
The moves will save the company $1 billion per year starting in 2010. Combined with previous efforts, GM by 2011 will have cut costs by $15 billion a year compared with 2005, Wagoner said.
GM shares rose 39 cents, or 2.2 percent, to $17.83 in morning trading.
The cuts will affect about 2,500 workers at each of the four facilities, although Wagoner did not know exact numbers. Many will be able to take openings created when 19,000 more U.S. hourly workers leave later this year through early retirement and buyout offers.
He said the company has no plans to allocate products to the four plants in the future.
"We really would not foresee the likely prospect of new products in the plants that we're announcing today that we'll cease production in," he told a Moraine, Ohio, city official who asked a question in a telephone conference call.
Wagoner said General Motors Corp.'s board approved the production schedule of the Chevrolet Volt, and the company plans to bring the plug-in electric car to showrooms by the end of 2010.
Fully charged, the Volt could drive about 40 miles without using any gasoline, and a small conventional engine would recharge the vehicle, extending its range and allowing it to get the equivalent of 150 miles per gallon. GM plans to sell about 100,000 Volts a year by 2012.
Wagoner said the change in the U.S. market to smaller vehicles likely is permanent. "We at GM don't think this is a spike or a temporary shift," Wagoner said.
On the Hummer, Wagoner said GM is "undertaking a strategic review of the Hummer brand, to determine its fit with GM's evolving product portfolio" in light of changing market conditions.
"At this point, we are considering all options for the Hummer brand... everything from a complete revamp of the product lineup to partial or complete sale of the brand," he said.
Detroit's automakers have been making the shift to more fuel-efficient vehicles, but not at the pace that matches consumers' drive to hybrids and high mileage models made overseas. Gas prices have accelerated the retreat from trucks and sport utility vehicles, leaving the Big Three at the most critical crossroads in 30 years.
The U.S. market is difficult for every automaker, with consumer confidence weak and 2008 sales expected to be the lowest in more than a decade. But it is most difficult for the Detroit Three, who have relied more heavily on sales of trucks and SUVs than their foreign counterparts. Trucks make up 70 percent of Chrysler LLC's U.S. sales, for example, compared to 41 percent at Toyota Motor Corp.
GM President and Chief Operating Officer Fritz Henderson said the new small car to be built in Lordstown would get 9 miles per gallon better fuel economy than the company's current small cars, the Chevrolet Cobalt and Pontiac G5 when equipped with a manual transmission. The most efficient Cobalt now gets 36 miles per gallon on the highway. Henderson would not give a total mileage number.
It would be powered by a 1- to 1.4-liter four-cylinder gasoline engine that could be turbocharged for additional power, GM said. The new engine would be built in Flint, Mich.
Henderson said the plant closure measures would reduce the company's capacity to produce pickups and large SUVs by 700,000 per year, about 35 percent.
He also said GM is planning for gasoline prices to stay around $4 per gallon for the foreseeable future, "with a bias upwards."
When asked if GM should have moved more quickly to smaller vehicles, Henderson said he doesn't spend time looking in the rearview mirror.
"There's not much I can do about what I didn't do in the past," he said.
Pete Hastings, senior analyst with Memphis, Tenn.-based Morgan Keegan & Co., said GM's moves are painful yet prudent.
"It's a permanent shift, and they're right to recognize it," he said. "But is it enough? It's a bit early to tell. ... That's the hard part of gauging where we are in the economy -- and how deep or strong the shift in demand is for more fuel-efficient vehicles."
Analyst Kevin Tynan of New York-based Argus Research Corp. said the Detroit Three automakers have been "caught with the market running away from them." While he recognizes GM's plight and efforts to overcome it, he still questions the aggressive push to market with the Volt, which is demanding heavy investment at a time when money is tight.
"It's very bad timing, very late in the game to be making big bets," he said. "At the same time, you don't have a choice."
The announcement is an economic blow to Janesville, which long has been entwined with automaking. The sprawling GM plant has survived the Depression, a world war and GM's major layoffs in the 1980s, but it will not escape the latest round of corporate belt-tightening.
"There were some tears and a lot of people were kind of ticked off, but it's part of the business," said Scott Lambert, 39, who has worked at the plant for 13 years.
He said he was headed to buy an atlas to figure where other GM plants were that might be hiring.
The plant, GM's oldest, opened in 1919 and long was the largest employer in Janesville, a city of 60,000 about 100 miles northwest of Chicago. But cutbacks have shrunk the work force to about 2,600, so it's no longer the city's biggest employer.
GM also has just emerged from a spate of labor problems, with two local union strikes at key factories and a nearly three-month strike at key parts maker American Axle and Manufacturing Holdings Inc.
GM said in a recent regulatory filing the strikes will cost it a total of $2 billion before taxes in the second quarter.