My van makes a hooting or moaning noise from the front and to the rear of the van. Passenger side. Grandson thinks it is the brakes, maybe air, or possibly my husband put the wrong fluid in the brake fluid reservoir. Brakes work ok, but noises seems to happen when braking or letting up on the brakes
If no one in your family knows what the brake problem is and fluid had to be added then off to the brake shop. Brakes are kind of important.