A dual earth starter motor for a vehicle. The starter motor includes a housing, an armature within the housing, a brush plate within the housing arranged to deliver electric current, by means of conductive brushes, to the armature, and two separate earth terminals electrically connected to the brush plate with each terminal extending through a wall of the housing. In a preferred form, the two earth terminals are electrically isolated from the housing, and at least one of the terminals is mechanically and electrically coupled to the brush plate my means of an interference fit between a portion of the terminal and a hole formed in the brush plate. A method of retrofitting a second earth terminal to an existing starter motor is also disclosed.