Subaru has changed the automatic transmission strainer from metal to a resin product. The bolt length and torque specifications also have changed. This affects 2005 and later Legacy/Outback and Impreza 2.5L, 2006 and later Impreza Turbo, 2004 and later Forester Turbo and 2005 and later Forester 2.5L models, equipped with the 4AT automatic transmission.
The new style (resin) strainer was used in production toward the end of October 2008, starting with transmission # 374122.
The old (metal) strainer is listed as P/N 31728AA091. The new (resin) strainer is listed as P/N 31728AA130.
Replacement new style (resin) strainer includes new bolts. The torque specification for the new style (resin) strainer is 3.4 ft.-lbf. (4.6 Nm). The bolt torque for bolts with the metal strainer is 7.4 ft.-lbf. (10 Nm).
The strainers (metal or resin) are interchangeable for the models listed here, but the correct bolts and torque specifications must be used.