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.
2016 Subaru WRX BaseFACTORY OEM SERVICE PROCEDURE
Extension Case: Installation
WARNING: This page is about a different variant/trim than selected.
- Clean the mating surface of the extension case and intermediate case.
- Select the rear drive shaft shim. < Ref. to ADJUSTMENT , Rear Drive Shaft. >
- Select the shim for transfer reduction driven gear. < Ref. to ADJUSTMENT , Transfer Reduction Driven Gear. >
- Install the selected rear drive shaft shims to the rear drive shaft.
- Attach the selected shim to transfer reduction driven gear assembly.
- Install the gasket and the extension case.NOTE: Use a new gasket.
Tightening torque:
25 N.m (2.5 kgf-m, 18.4 ft-lb)
- Install the rear wheel speed sensor. < Ref. to INSTALLATION , Rear Wheel Speed Sensor. >
- Install the front wheel speed sensor. < Ref. to INSTALLATION , Front Wheel Speed Sensor. >
- Install the transmission assembly. < Ref. to INSTALLATION , Automatic Transmission Assembly. >
Factory Service Tools
Use the Manual With the Right Hardware
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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.