Front Brake

Apply ATF to D-ring, and then install it to the front brake piston.
Install the front brake piston to oil pump cover.
NOTE: Install by aligning the "Δ" mark on front brake piston surface with the oil pump cover rib.

Fig 1: Identifying Mark And Front Brake Piston To Oil Pump Cover Rib
Courtesy of SUBARU OF AMERICA, INC.
Install the retainer and return spring.
Install the front brake piston assembly using ST1, ST2 and ST3.
ST1 18762AA000 COMPRESSOR SPECIAL TOOL

ST2 18765AA000 COMPRESSOR SUPPORT

ST3 18763AA000 COMPRESSOR SHAFT

Fig 2: Identifying Snap Ring Using ST1, ST2 And ST3
Courtesy of SUBARU OF AMERICA, INC.
Install the genuine driven plate instead of retainer plate, and temporarily assemble the drive plate and driven plate.
Part No. 31536AA290 DRIVEN PLATE
Install the snap ring.

Fig 3: Identifying Snap Ring
Courtesy of SUBARU OF AMERICA, INC.

Measure the clearance between retainer plate and snap ring, and then select the suitable retainer plate from table.

Front brake clearance specification:

0.7 - 1.1 mm (0.028 - 0.043 in)

Fig 4: Measuring Clearance Between Retainer Plate And Snap Ring

Courtesy of SUBARU OF AMERICA, INC.

THICKNESS SPECIFICATION CHART

Remove the snap ring, replace the driven plate used in measurement of clearance with the retainer plate, and then reassemble.