Is buying a car through the bank—where the bank pays the remaining amount to the dealership and the customer repays it in installments, with a prohibition on selling the car and the bank owning it until the installments are paid off—considered usury (riba) or a deferred sale?

The transaction mentioned in the question—which the questioner refers to as a car loan—is forbidden in Islamic law because the bank lends the customer the remaining amount for the car's price, to be repaid with an increase that it calls interest. Every loan conditioned on an increase is unanimously forbidden.