DETROIT—Chrysler will add 1,250 jobs at two Detroit factories next year.

The Detroit-based automaker will add 1,100 people to its Jefferson North factory—wher it assembles the Jeep Grand Cherokee—to build a diesel model for North America next year.

The plant will get a third shift of workers.

The company will also create 150 jobs by reopening the Conner Avenue factory to manufacture a Street Racing Team version of the Dodge Viper muscle car.