Dissimilar Metals Cause Corrosion

Doing a post update about the effects salt and 2 dissimilar metals. Aluminum and steel are our 2 most common found metals on automobiles. Unfortunately they do not agree when put next to each other with salt added in. The bolts that were supposed to hold these truck running boards on came out due to the bolts being steel with aluminum boards. You can see in the picture below how the aluminum corroded away around the bolts. New hardware and repositioning the boards allowed us to save the boards so the customer did not have to buy new ones. This same issue also happens on other parts of a car. The most common is on exhaust heat shields, causing rattles as the shields contact the pipes.