Abstract: A wet disc brake and axle fluid cooling assembly is disclosed which is driven by a vehicle's axle shaft. The system comprises a brake housing, an axle shaft connected to the brake housing wherein the brake fluid can flow between the brake housing and the axle housing, an internal pump connected to the axle housing, and an external cooling tube disposed between the internal pump and the brake housing. An axle shaft is rotatingly disposed within the axle housing. A first spur gear is connected to and rotates with the axle shaft. The internal pump is comprised of an axle straight tee fitting, a pump rod rotatingly connected to the tee fitting, a propeller connected to and rotating with the pump rod that draws the fluid from either the axle housing or the brake housing, and a second spur gear that engages with the first spur gear. The axle shaft drives the pump rod as the shaft rotates, either clockwise or counter-clockwise.