The wheel arches in every car are prone to rust due to natural elements such as rain and mud and being exposed to road salt during winter. Rust can go on undetected especially when hidden under fender flares. Being proactive is the way to go when it comes to rust, so you need to take the necessary precautions prior to installing your newly purchased flare kit. This means inspecting the wheel well and spraying on sealant in rust prone areas.