A rear sliding window assembly suitable for use in a vehicle includes a fixed portion and a sliding portion and upper and lower track members disposed at a surface of first and second fixed glass portions. The sliding portion comprises a glass window panel and is laterally movable between the upper and lower track members relative to the fixed portion. The glass window panel is movable between an opened position and a closed position, and the glass window panel is disposed at the gap that is between the first and second fixed glass window portions when at its closed position. A glide member is longitudinally movable along the lower track member to facilitate movement of the glass window panel between its opened and closed positions. A sealing member is disposed between the fixed portion and the sliding portion at least when the glass window panel is at its closed position.