An operating material supply system for a motor vehicle includes: i) at least one operating material container for storing operating material at risk of freezing; ii) at least one conveying device, which is designed to convey the operating material stored in the operating material container upstream in the direction of at least one injector, or in the opposite direction downstream, iii) at least one air separator, which is connected to the operating material container via a feed line; iv) at least one first injector line, which connects the air separator to at least one first injector. When the air separator is installed in the motor vehicle, a connector for the first injector line is distanced further from the roadway surface than a connector for the feed line.