Castrol Transmax DEX/MERC is designed for use in older GM and Ford vehicles and meets both DEXRON®-IIIH and MERCON® requirements. Exceeds all passenger car and light truck manufacturer’s warranty requirements for vehicles, transmissions or power steering service where a DEXRON-IIIH or MERCON type ATF is specified. Meets or exceeds the following requirements: ATF+3, MERCON, DEXRON IIIH.