Underbody MaintenanceChemicals used for ice and snow removal and dustcontrol can collect on the underbody. If these are notremoved, corrosion and rust can develop on theunderbody parts such as fuel lines, frame, floor pan andexhaust system even though they have corrosionprotection.At least every spring, flush these materials from theunderbody with plain water. Clean any areas where mudand debris can collect. Dirt packed in close areas ofthe frame should be loosened before being flushed.Your dealer or an underbody car washing system cando this for you.Chemical Paint SpottingSome weather and atmospheric conditions can create achemical fallout. Airborne pollutants can fall upon andattack painted surfaces on your vehicle. This damagecan take two forms: blotchy, ring-shaped discolorations,and small, irregular dark spots etched into the paintsurface.Although no defect in the paint job causes this, GM willrepair, at no charge to the owner, the surfaces ofnew vehicles damaged by this fallout condition within12 months or 12,000 miles (20 000 km) of purchase,whichever occurs first.5-81
