Abstract: An improved aftertreatment support assembly is disclosed. The support assembly includes a mounting plate that may be adapted to be affixed above an engine, and may be used to support engine exhaust aftertreatment components, including particulate filters and catalytic converters. The mounting plate may include front and rear isolation mounts, and each mount may incorporate an elastomeric vibration absorbing bushing. The mounting plate may be attached to either or both of an engine block or flywheel housing by means of brackets, each of which may be affixed to one of the mounts. In one disclosed embodiment, the mounting plate and brackets may be formed of stamped metal components, and at least one pair of the mounts may share a common bracket.