Isolation seals for gas turbine engines are described. The isolation seals include a first interface member configured to be fixedly attached to a first case structure, the first interface member being a full-hoop structure, a housing configured to be mounted to a second case structure, a connector pin arranged within the housing and moveable relative to the housing, and a second interface member located on an end of the connector pin, the second interface member being a full-hoop structure. The first interface member and the second interface member are engageable to form a seal therebetween.