Toyota says it's investing $1.3 billion to retool its sprawling Georgetown, Kentucky, factory where its flagship Camry sedans are built.

The automaker said Monday that no new factory jobs are being added, but the investment will sustain the existing 8,200 jobs at Toyota's largest plant, where nearly one-fourth of all Toyota vehicles produced in North America are made.

Toyota says the upgrades amount to its biggest single investment ever at an existing plant in the United States.

The factory-wide upgrade in Kentucky comes as Toyota is preparing for production of the revamped 2018 Camry featuring a new exterior design, an upgraded interior and a new engine.

The Kentucky plant also assembles the Avalon and the Lexus ES 350.