Will this scrape on steep driveways or inclines?

Measure your current ride height and compare it to the downward extension of your bumper baseline. This diffuser attaches to the existing rear bumper assembly, so ground clearance depends on your vehicle's current suspension setup and any lowering modifications. Test approach angles before committing to a finish if you frequent steep parking areas.

Is this functional or purely cosmetic?

The channeled design supports aerodynamic function by managing airflow separation at highway speeds. Whether you prioritize that airflow benefit or the visual stance, the performance gain is subtle on street vehicles and scales with track use.

What prep and finish do I need before installation?

Sand the surface with appropriate grit for your chosen topcoat, then apply your preferred automotive paint, clear coat, or protective finish. Install once the finish is fully cured per your paint manufacturer's instructions.