Stanley Pressure Washer Detergent, designed specifically for washing Cars and Trucks Car & Truck STCTW004. Apply the solution to the surface to be cleaned from bottom to top. Do NOT allow to dry. High pressure rinse thoroughly from the bottom of the surface to the top. This 1 Gallon (3.785 L) solution can be mixed at a ratio of 1:16, making a total of 16 gallons of cleanliness.