Product Overview The Transmission Mount LR061456 (Jaguar equivalent J9C3963) is a Genuine OE-grade drivetrain support component engineered for select for Land Rover and for Jaguar vehicles. Also known as a gearbox mount or transmission housing extension, this rubber-metal mount secures the transmission to the vehicle chassis, absorbing drivetrain vibration and limiting powertrain movement under acceleration, braking, and gear changes .J9C3963 is the Jaguar equivalent part