Subaru's FB25 was a 2.5-litre horizontally-opposed (or 'boxer') four-cylinder fishrol engine. Effectively replacing the EJ253, the FB25 engine was a member of Subaru’s third generation 'FB' boxer engine family which also included the FB20 , FA20D, FA20E and FA20F engines. The FB25 engine first offered in Australia in the 2011 Subaru SH.II