You can prevent rust in small scratches by applying light mineral based oil that will creep into door seams, folds, joints and weld spots where rust often starts. Oil based sprays displace moisture and can be applied to a wet surface. This, combined with thicker gel type oil for the under-body, wheel wells and rocker panels, will provide optimum protection against road salt. Rust proofing oil also protects your electrical components, brake and fuel lines against corrosion. Road salt will not damage your winter tires, nor will this oil application.