A compliant seal assembly that may be for an MTF of a gas turbine engine includes a housing orientated about an axis with a circumferentially extending groove in the housing opened radially outward. An annular carrier of the assembly is constructed and arranged to move radially within the groove, and includes a circumferentially extending channel that is opened radially outward for receipt of a piston ring that may seal to a surrounding cylindrical wall. In operation, the carrier moves radially with respect to the housing to compensate for radial displacement between the housing and the wall, and the piston ring moves axially along the wall to compensate for axial displacement between the housing and the wall.