How to Replace the Serpentine Belt on a 2013 Subaru Forester (Step-by-Step Guide)
Tools, parts, belt routing tips, safety precautions, and final checks to stop squealing or slipping for 2011, 2012, 2013
How to Replace the Serpentine Belt on a 2013 Subaru Forester (Step-by-Step Guide)
Tools, parts, belt routing tips, safety precautions, and final checks to stop squealing or slipping for 2011, 2012, 2013
š§ Forester - Serpentine Belt Replacement
Your Foresterās serpentine belt drives the alternator and A/C. Replacing it restores proper grip and prevents squealing, slipping, or a sudden loss of charging.
Difficulty Level: Beginner | Estimated Time: 0.5-1.0 hours
ā ļø Safety & Precautions
- ā ļø Work on a cool engine; keep hands away from fans and pulleys.
- ā ļø Remove keys from the vehicle so no one can start it.
- ā ļø Keep fingers clear when releasing the tensioner; it snaps back strongly.
- ā ļø Battery disconnect is not required, but itās okay to disconnect the negative terminal if you want extra safety.
š§ Required Tools
You'll need the following tools for this repair:
- 10mm socket
- 3/8" drive ratchet
- 3/8" drive breaker bar
- 14mm socket
- Torque wrench (inch-pound or low-range)
- Flat trim clip tool
- Flashlight
- Mechanic gloves
- Safety glasses
š© Required Parts
HowToo sells all the parts you need for this repair:
- Serpentine belt - Qty: 1
š Before You Begin
- Park on level ground, shift to Park, and set the parking brake.
- Open the hood and let the engine cool fully.
- Find the belt routing diagram (usually a sticker under the hood). If itās missing, take a clear photo of the current routing before removing the belt.
- If you choose to disconnect the battery: use a 10mm socket to loosen the negative terminal and move it aside so it canāt spring back.
šØ Step-by-Step Instructions
Follow these steps in order:
Step 1: Remove the engine cover (if equipped)
- Use a 10mm socket and 3/8" drive ratchet to remove the engine cover fasteners.
- If your cover uses push-clips, lift them with a flat trim clip tool.
- Set the cover and fasteners aside.
Step 2: Locate the belt tensioner and confirm routing
- Use a flashlight to look at the belt path around each pulley.
- Locate the automatic tensioner (a spring-loaded arm that keeps belt tension by itself).
- Take a photo for easy reassembly.
Step 3: Release belt tension
- Install a 14mm socket on the tensionerās hex boss/bolt head.
- Use a 3/8" drive breaker bar to rotate the tensioner to relieve tension (it will feel strong).
- While holding the tensioner rotated, slide the belt off one easy pulley (usually the alternator at the top).
- Slowly let the tensioner return to its resting position. Do not let it snap back.
Step 4: Remove the old belt and inspect pulleys
- Pull the belt out of the engine bay.
- Use a flashlight to inspect pulleys for wobble, cracks, or heavy rust.
- Spin any smooth idler pulleys by hand (engine OFF). They should feel smooth and quiet.
Step 5: Install the new belt
- Route the new belt following the under-hood diagram (or your photo).
- Make sure the ribbed side of the belt sits in the ribbed pulleys, and the smooth side rides on smooth pulleys.
- Leave the belt off one easy pulley (again, usually the alternator) for last.
- Use the 14mm socket and 3/8" drive breaker bar to rotate the tensioner and slip the belt onto the last pulley.
- Slowly release the tensioner so it takes up the belt.
- Double-check every pulley: the belt ribs must be fully seated in the grooves.
Step 6: Reinstall the engine cover (and reconnect battery if removed)
- Reinstall the engine cover using a 10mm socket and 3/8" drive ratchet.
- If you disconnected the battery, reconnect the negative terminal using a 10mm socket and torque wrench: Torque to 7.5 Nm (66 in-lbs).
ā After Repair
- Start the engine and let it idle while you watch the belt track (keep hands/tools away from moving parts).
- Listen for squealing, chirping, or slapping noises.
- Turn the A/C on and off and re-check for noise changes.
- After a short drive, do a quick recheck to confirm the belt is still centered on every pulley.
š° DIY vs Shop Cost
Shop Cost: $150-$250 (parts + labor)
DIY Cost: $25-$50 (parts only)
You Save: $100-$200 by doing it yourself!
Shop labor rates vary but typically run $100-$150/hour. This repair takes a shop approximately 0.5-1.0 hours.
šÆ Ready to get started?
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