The Salt and High-Humidity Test
To compare real-world rust-resistance, Subaru engineers reproduced the effects of salt and high humidity on the fenders in a snowfall region* for one year. As the photos show, the layer of zinc galvanization and the thickness of the electrolytically applied paint gave the Genuine Subaru fender the edge. SCRATCHES The salt and humidity clearly took a greater toll on the spot where the aftermarket fender was scratched. The Genuine Subaru's zinc galvanization protected it against any rust damage.
FENDER EDGES AND MOUNTING BOLT HOLES
The salt and humidity also caused damage on the aftermarket fender edges and around the mounting bolt holes. The rust is heavier along the edges where the electric deposition coating is thinnest. The Genuine Subaru fender stayed rust-free on the inside and outside surfaces.
* Test included immersing fenders in salt, plus drying and humidifying