Can I run Dawn dish soap through my pressure washer?

Can I run Dawn dish soap through my pressure washer?

Technically you can, but most pressure washer manufacturers advise against it, and it’s not the ideal choice. Dawn and similar dish soaps are formulated to create thick suds, which can clog a pressure washer’s detergent injection system, reduce suction, and in some cases put extra strain on the pump over time. If you do use it, dilute heavily — roughly 1–2 ounces per gallon of water — and flush the system with clean water afterward to prevent residue buildup. A safer middle ground is running Dawn through a separate foam cannon attachment instead of the machine’s built-in detergent tank, since a foam cannon bypasses the pump entirely. For regular use, a detergent specifically formulated for pressure washers is the safer, manufacturer-approved choice, since it’s designed to rinse cleanly without leaving residue or risking internal damage.