"In a sign of Toyota's new-found muscle, the Japanese automaker rattled Detroit by offering zero-percent financing and cash rebates on its all-new Tundra pickup truck in June.
That aggressive discounting caused sales of Toyota's new full-size truck to more than double in June, stealing share in the last U.S. market segment dominated by the Detroit Three."

Looks like Tundra sales were boosted by the incentives.