This document establishes recommended practices to validate acceptable corrosion performance of metallic components and assemblies used in medium truck@ heavy truck@ and bus and trailer applications. The focus of the document is methods of accelerated testing and evaluation of results. A variety of test procedures are provided that are appropriate for testing components at various locations on the vehicle. The procedures incorporate cyclic conditions including corrosive chemicals@ drying@ humidity@ and abrasive exposure. These procedures are intended to be effective in evaluating a variety of corrosion mechanisms as listed in Table 2. Test duration may be adjusted to achieve any desired level of exposure. Aggravating conditions such as joint rotation@ mechanical stress@ and temperature extremes are also considered. This document does not address the chemistry of corrosion or methods of corrosion prevention. For information in these areas@ refer to SAE J447 or similar standard.