A critical step in protecting aluminum alloys from corrosion is surface pretreatment. According to ASTM D-1730, many combinations of acid, alkaline, or solvent cleanings may be used and regarded as acceptable methods for pretreatment of aluminum alloys before painting. Flexibility in controlling the steps in the standard has lead to a high number of pretreatments, many of which have not been studied fundamentally to understand their effects on corrosion protection. X-ray photoelectron spectroscopy (XPS), Auger electron spectroscopy (AES), and scanning electron microscopy (SEM) were used to study seven combinations of surface treatments on Al 2024-T3 (UNS A92024). It was found that phosphoric acid (H3PO4) treatment greatly affected the concentration of copper at the alloy surface. It also was found that polishing and acid treatment increased alloy deterioration.