Will this interfere with the trunk seal or rear bumper fitment?

The diffuser is designed to integrate with the factory rear bumper assembly. Before installation, confirm clearance with your bumper's trailing edge and verify the mounting point locations match your vehicle's OEM hole pattern. If custom drilling is required, start with a test fit and mark holes carefully.

Should I use adhesive, bolts, or both to secure this?

FRP diffusers perform best when mechanically fastened through existing or drilled mounting points. Adhesive alone is not recommended for rear bumper loads. Use corrosion-resistant fasteners (stainless steel or plated) and consider a gasket seal at high-stress contact points to minimize vibration and water intrusion.

Will the diffuser stay stable at highway speeds?

Yes, when properly fastened through solid mounting points and secured with appropriate hardware. Ensure all fasteners are tight before driving, and check them after the first 50 miles. Road vibration can loosen bolts over time; periodic inspection keeps the panel secure and prevents rattling or movement.