What must be done before applying the 90-day wax in the Express Detail?

Before applying the 90-day wax in the Express Detail, it is essential to wash the vehicle thoroughly. This step is crucial because any dirt, grime, or debris left on the surface can prevent the wax from bonding properly to the paint. Washing the vehicle ensures that the surface is clean and free of contaminants, allowing for better adhesion and a more effective protective layer once the wax is applied. This process enhances the durability and performance of the wax, ultimately leading to better protection of the vehicle’s finish.

While other actions like drying the vehicle or applying interior cleaner are important steps in detailing, they come after or are not directly related to the application of the wax itself. Therefore, washing the vehicle first is the foundational step that directly impacts the effectiveness of the wax application.