🔧 Outback - Serpentine Belt Replacement

The serpentine belt (also called the accessory drive belt) spins key accessories like the alternator and A/C. On your Outback, the belt is held tight by an automatic belt tensioner (a spring-loaded pulley that keeps proper belt tension), so you don’t “adjust” it—you rotate the tensioner to slip the belt on and off.

Difficulty Level: Intermediate | Estimated Time: 0.5-1.5 hours

---

⚠️ Safety & Precautions

• ⚠️ Work on a cold engine to avoid burns near the radiator and exhaust.
• ⚠️ Keep fingers clear of pulleys while rotating the tensioner (it can snap back hard).
• ⚠️ If you lift the vehicle, support it with jack stands (never rely on a jack).
• ⚠️ Do not start the engine until the belt is fully seated on every pulley.

---

🔧 Required Tools

You'll need the following tools for this repair:

• Safety glasses
• Mechanic gloves
• Flashlight
• 3/8" drive ratchet
• 3/8" drive breaker bar
• Serpentine belt tool (specialty)
• 14mm socket
• 10mm socket
• Trim clip removal tool
• Flathead screwdriver
• Floor jack (rated 3-ton minimum)
• Jack stands (rated 3-ton minimum)
• Wheel chocks
• 19mm socket
• Torque wrench (10-150 ft-lbs range)

---

🔩 Required Parts

HowToo sells all the parts you need for this repair:

• Serpentine belt (accessory drive belt) - Qty: 1
• Belt tensioner assembly - Qty: 1 Optional if noisy/weak
• Idler pulley - Qty: 1 Optional if bearing noisy

---

📋 Before You Begin

• 🧰 Park on level ground, shift to Park, and set the parking brake.
• 🧰 Let the engine cool fully.
• 🧰 Take a quick photo of the belt routing diagram (usually on a sticker in the engine bay). If the sticker is missing, sketch the routing before removing the belt.
• 🧰 If you choose the wheel-well access method, chock the rear wheels before lifting.

---

🔨 Step-by-Step Instructions

Follow these steps in order:

Step 1: Confirm belt routing

• Use a flashlight to locate the belt routing sticker and compare it to what you see.
• If you can’t find a sticker, use your phone to take multiple photos from different angles.
• Photos prevent routing mistakes.

Step 2: Choose your access path

• Top access (preferred): You’ll work from above using a serpentine belt tool (specialty) (a long, thin handle that fits in tight spaces).
• Wheel-well access (if space is tight): You’ll remove the right-front wheel and inner splash access to reach the tensioner more easily.

Step 3 (Wheel-well access only): Lift and remove the right-front wheel

• Place wheel chocks behind the rear wheels.
• Use a 19mm socket and breaker bar to loosen the lug nuts 1/2 turn while the wheel is on the ground.
• Lift with a floor jack (rated 3-ton minimum) and support with jack stands (rated 3-ton minimum).
• Remove the lug nuts using a 19mm socket and remove the wheel.
• On reinstall: Torque to 120 Nm (89 ft-lbs).

Step 4 (Wheel-well access only): Remove the splash shield access

• Use a trim clip removal tool and flathead screwdriver to remove plastic clips carefully.
• Use a 10mm socket to remove any small bolts holding the access panel.
• Reinstall snugly (plastic panels/clips do not have a torque spec).

Step 5: Relieve tension from the automatic tensioner

• Locate the belt tensioner pulley and the wrench point on the tensioner arm.
• Install a 14mm socket on a serpentine belt tool (specialty) (or a 3/8" drive breaker bar if it fits).
• Rotate the tensioner smoothly to unload the belt, then hold it there.
• Move slowly—spring force is strong.

Step 6: Remove the old belt

• While holding the tensioner rotated with the serpentine belt tool (specialty), slip the belt off the easiest-to-reach top pulley first.
• Slowly release the tensioner back to its resting position.
• Remove the belt from the remaining pulleys by hand.

Step 7: Inspect pulleys and tensioner

• Spin each pulley by hand and listen/feel for roughness or grinding.
• Check the tensioner pulley for wobble or leakage at the bearing area.
• If any pulley feels rough or noisy, plan to replace the pulley/tensioner before installing the new belt.

Step 8: Install the new belt (route first, then tension last)

• Route the new belt around the pulleys following the under-hood diagram.
• Make sure the belt ribs sit fully into the grooved pulleys (no “one-rib off” misalignment).
• Leave the easiest pulley for last (usually an upper smooth pulley).

Step 9: Apply tension and seat the belt

• Rotate the tensioner again using the 14mm socket and serpentine belt tool (specialty).
• Slip the belt onto the last pulley, then slowly release the tensioner.
• Re-check every pulley with a flashlight to confirm the belt is centered and fully seated.

Step 10: Reassemble (if removed)

• Reinstall splash shield/access using a 10mm socket and trim clip removal tool.
• Reinstall the wheel using a 19mm socket.
• Lower the vehicle and final-tighten lug nuts with a torque wrench: Torque to 120 Nm (89 ft-lbs).

---

✅ After Repair

• Start the engine and let it idle while you watch the belt for 30-60 seconds (keep hands and clothing clear).
• Listen for squealing, chirping, or clicking (signs of misrouting or a failing pulley bearing).
• Turn A/C on and off and confirm the belt runs smoothly with no wandering.
• After a short test drive, recheck belt alignment with a flashlight.

---

💰 DIY vs Shop Cost

Shop Cost: $180-$350 (parts + labor)

DIY Cost: $35-$90 (parts only)

You Save: $145-$260 by doing it yourself!

Shop labor rates vary but typically run $100-$150/hour. This repair takes a shop approximately 0.7-1.2 hours.

---

🎯 Ready to get started?

HowToo makes it easy: same-day/2-day shipping on every part, plus all the tools and specialty tools you need! Check out the parts and tools sections below to add everything to your cart.