Will the diffuser scrape on steep driveways or inclines?

Clearance depends on your suspension setup and driveway angle. Measure the gap between your current rear bumper and ground at full compression, then compare against the diffuser's lower edge profile. Most owners with stock ride height report no scrape on typical residential grades.

Is this diffuser functional or cosmetic?

The GMX design features integrated vanes that manage low-pressure zones behind the rear bumper, providing aerodynamic benefit at highway speeds and during aggressive driving. It's not a placeholder — the diffuser geometry contributes to rear-end stability, though the visual impact is equally important to the airflow function.

What prep work do I need before painting?

Sand the surface with appropriate automotive sandpaper and wipe clean with a tack cloth before applying your chosen base coat and clear. FRP accepts standard automotive finishes, but avoid heavy sanding pressure to prevent chipping the gelcoat below the primer layer.