A gate valve, comprising: a gate movable between open and closed positions within a valve body; and walls in the gate defining an equalizer port between opposite external sealing faces of the gate, with the equalizer port adapted and arranged to be shiftable by actuation of the gate between closed and opened positions and between opened and closed positions, with internal faces (48,50) forming a cavity within the gate, and with the equalizer port being in at least one shiftable equalizer gate within the cavity, and with the equalizer port being within a carrier within the cavity of the gate, the carrier being movable between opening and closing positions and connected for linear actuation, characterised in that the carrier has side surfaces spaced to closely interfit with adjacent internal side faces (52,54) of the cavity within the gate for sliding linear relative movement within the cavity and in that the carrier has two opposite end surfaces (88, 90), the end surfaces (88, 90) having a linear distance between them less than a linear distance between internal end faces (48,50) of the cavity, such that the carrier has a range of linear travel within the cavity during linear actuation between the opening and closing positions, with one end surface contacting one cavity internal end face in the opening position, and with the other end surface contacting the other cavity internal end face in the closing position, such that the carrier end surfaces in contact with the respective internal end faces (56,58) of the cavity are operative to move the gate between the opened and closed positions. a gate movable between open and closed positions within a valve body; and walls in the gate defining an equalizer port between opposite external sealing faces of the gate, with the equalizer port adapted and arranged to be shiftable by actuation of the gate between closed and opened positions and between opened and closed positions, with internal faces (48,50) forming a cavity within the gate, and with the equalizer port being in at least one shiftable equalizer gate within the cavity, and with the equalizer port being within a carrier within the cavity of the gate, the carrier being movable between opening and closing positions and connected for linear actuation, characterised in that the carrier has side surfaces spaced to closely interfit with adjacent internal side faces (52,54) of the cavity within the gate for sliding linear relative movement within the cavity and in that the carrier has two opposite end surfaces (88, 90), the end surfaces (88, 90) having a linear distance between them less than a linear distance between internal end faces (48,50) of the cavity, such that the carrier has a range of linear travel within the cavity during linear actuation between the opening and closing positions, with one end surface contacting one cavity internal end face in the opening position, and with the other end surface contacting the other cavity internal end face in the closing position, such that the carrier end surfaces in contact with the respective internal end faces (56,58) of the cavity are operative to move the gate between the opened and closed positions.