Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
2021 Subaru Forester BaseFACTORY OEM SERVICE PROCEDURE
Differential Side Retainer
- Install the new differential side retainer oil seal using the ST.NOTE:
- Apply differential gear oil to the differential side retainer oil seal lip.
- Since the differential side retainer oil seal has an identification mark (R or L), be careful not to mix up the RH and LH when installing.
Preparation tool:
ST: DIFFERENTIAL SIDE OIL SEAL INSTALLER (18675AA000)
- Install a new O-ring.NOTE: Apply the differential gear oil to O-ring.
Factory Service Tools
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.