New 25% tariffs on auto imports could cost US carmakers up to $10,000 per vehicle.Porsche, Mercedes-Benz, Stellantis, and Volkswagen are expected to be the hardest-hit by these tariffs.The tariffs could lead to credit quality weakening and potential price increases for vehicles in the US market.Moving production to the US to offset the tariff impact would be costly and time-consuming for car companies.