DETROIT (AP) — General Motors plans to invest $332 million into four factories in three Great Lakes states to build new, more efficient engines and transmissions.

The spending at plants in Toledo, Ohio; Bedford, Ind.; and Flint and Bay City, Mich., will allow the company to build a new V-6 engine, a new small motor and new eight-speed automatic transmissions, GM said Thursday. The company also added $46 million to a prior investment at plants in Romulus and Saginaw, Mich. to build the new V-6.

No jobs will be added, but GM said the investments preserve 1,650 jobs at the six factories.

The investment also will help GM build more six-speed automatic transmissions as auto sales continue to rise in the U.S. Sales this year are expected to climb as high as 15.5 million cars and trucks, 1 million more than last year. Through March, GM sales are up just over 9 percent.

GM wouldn't give details about the new engines and transmissions, nor would it say what cars and trucks would get the new powertrains. It also wouldn't say exactly when they would be available, for fear of tipping competitors to its product plans.

The company did say that the money will help start a new family of three- and four-cylinder engines that range from 1 liter to 1.5 liters. Presently the smallest motor GM makes in the U.S. is a turbocharged 1.4-liter four-cylinder that goes into the Chevrolet Cruze and Sonic, as well as other models.

Last summer CEO Dan Akerson told employees that the company was behind its competitors in engines and transmissions, saying that GM has six-speed transmissions when competitors have up to 10 gears. Transmissions with more gears allow engines to do less work and save fuel.

The investments announced Thursday should improve GM's technology in relation to its competitors, said Arvin Jones, GM North America manufacturing manager. "We think the investments we're making will give us a competitive advantage and position us very well," he told reporters.

The investments are part of $1.5 billion that GM plans to spend on its North American factories this year. So far the company has announced projects totaling $1.2 billion in the U.S. Another $250 million was announced for a GM assembly plant in Ingersoll, Canada.

The investments announced Thursday include:

— $215 million for the Flint Engine Operations in Flint, Mich., where the new three- and four-cylinder engines will be built. The plant also will get upgraded machinery for a V-6 engine that it currently builds.

— $55.7 million for Toledo Transmission Operations in Toledo, Ohio, to build a new eight-speed transmission and expand capacity to build an existing six-speed transmission. The new transmission will be used in "numerous" GM vehicles by the end of 2016, the company said in a statement.

— $31.7 million for a powertrain plant in Bay City, Mich., north of Detroit, to build parts for a new V-6 engine and components for new small engines.

— $29.4 million for a metal castings plant in Bedford, Ind., to make parts for small engines and for the new eight-speed and existing six-speed automatic transmissions.

GM already has announced that the new Cadillac CTS luxury sports sedan, due out later this year, will have an eight-speed automatic transmission that initially will be built by an outside company. The CTS also will get a new twin-turbo V-6 engine. New full-size Chevrolet and GMC pickup trucks that arrive late this spring also are expected to get eight-speed transmissions at a later date.