Described herein are pretreatment compositions, coated aluminum alloy products, and methods for coating the alloys. The pretreatment compositions include inorganic chemical corrosion inhibitors dispersed in a silane-based matrix and may further include clay particles. The inorganic chemical corrosion inhibitors include rare earth metals and salts thereof. The pretreatment compositions, when applied to the surface of an alloy, inhibit corrosion of the alloys. The pretreatment compositions can be used in automotive, electronics, industrial, transportation, and other applications.