🔧 Focus - Serpentine Belt Replacement

The serpentine belt (the long belt that drives the alternator and other accessories) wears out and can crack, squeal, or slip. On your Focus, you’ll replace it by accessing the belt from the right-front wheel well and releasing the automatic belt tensioner.

Difficulty Level: Intermediate | Estimated Time: 1-2 hours

Assumption: Access is through right-front wheel well with an automatic tensioner.

---

⚠️ Safety & Precautions

• 🧯 Work on a cool engine; keep hands clear of pulleys.
• 🧱 Support the car with jack stands; never rely on a floor jack alone.
• 🛑 Chock the rear wheels and keep the transmission in 1st gear with the parking brake set.
• 🔋 Battery disconnect is not required, but keep tools away from the alternator electrical connections.

---

🔧 Required Tools

You'll need the following tools for this repair:

• Floor jack (rated 2-ton minimum)
• Jack stands (rated 2-ton minimum)
• Wheel chocks
• 19mm socket
• 1/2" drive breaker bar
• 1/2" drive ratchet
• 3/8" drive ratchet
• 15mm socket
• 8mm socket
• 10mm socket
• Trim clip removal tool
• Flashlight
• Mechanic gloves
• Safety glasses

---

🔩 Required Parts

HowToo sells all the parts you need for this repair:

• Serpentine belt - Qty: 1
• Serpentine belt tensioner - Qty: 1 (optional if noisy/weak)
• Idler pulley - Qty: 1 (optional if noisy)
• Underbody splash shield clips - Qty: 1 set (optional if any break)

---

📋 Before You Begin

• Park on level ground, turn the engine off, and let it cool.
• Set the parking brake, put the shifter in 1st gear, and place wheel chocks behind the rear wheels.
• Take a quick photo of the belt routing (how it snakes around pulleys) before removal.

---

🔨 Step-by-Step Instructions

Follow these steps in order:

Step 1: Raise the right-front corner and remove the wheel

• Use a 19mm socket and 1/2" drive breaker bar to slightly loosen the right-front lug nuts.
• Lift the right-front corner using a floor jack (rated 2-ton minimum) at the proper jacking point.
• Set the car securely onto jack stands (rated 2-ton minimum).
• Remove the lug nuts with a 19mm socket and 1/2" drive ratchet, then remove the wheel.

Step 2: Remove the splash shield / access panel

• Use a flashlight to locate the lower splash shield and the small access area in the wheel well near the belt.
• Remove fasteners using an 8mm socket and 10mm socket with a 3/8" drive ratchet.
• Pop any plastic push-clips out using a trim clip removal tool (this tool slides under the clip and lifts it without breaking it).
• Move the shield aside to clearly see the belt, pulleys, and tensioner.

Step 3: Inspect belt routing and pulleys

• Use a flashlight to find each pulley the belt touches.
• Spin any easy-to-reach smooth pulleys by hand (engine off) and listen/feel for roughness.
• If the belt routing decal is present, note it; if not, use the photo you took earlier.
• If a pulley grinds, replace it now.

Step 4: Release the belt tensioner

• Locate the automatic tensioner (a spring-loaded arm with a pulley). The “automatic tensioner” keeps belt tension without manual adjustment.
• Install a 15mm socket on the tensioner’s hex (or bolt head) and attach a 1/2" drive breaker bar.
• Rotate the tensioner smoothly to relieve belt tension (you’ll feel spring force).
• While holding the tensioner rotated, slide the belt off the easiest-to-reach pulley.
• Slowly let the tensioner return to its resting position. Do not let it snap back.

Step 5: Remove the old belt

• Work the belt off the remaining pulleys by hand while watching that it doesn’t snag on wiring or hoses.
• Compare the old belt to the new belt for length and rib count before installation.

Step 6: Install the new belt (route it correctly)

• Route the new belt around the pulleys following your photo/routing diagram.
• Make sure the ribbed side of the belt sits fully into the grooves of ribbed pulleys.
• Leave the easiest pulley for last (often a smooth idler or the alternator pulley area).
• Misalignment will shred a belt fast.

Step 7: Re-apply tension and seat the belt

• Use the 15mm socket and 1/2" drive breaker bar to rotate the tensioner again.
• Slip the belt fully onto the last pulley, then slowly release the tensioner.
• Use a flashlight to double-check the belt is centered on every pulley and fully seated in grooves.

Step 8: Reinstall splash shield and wheel

• Reinstall the splash shield using a trim clip removal tool (to align clips), then tighten fasteners with an 8mm socket or 10mm socket using a 3/8" drive ratchet.
• Reinstall the wheel and hand-thread the lug nuts.
• Lower the car off the jack stands (rated 2-ton minimum) using the floor jack (rated 2-ton minimum).
• Tighten lug nuts in a star pattern using a 19mm socket and 1/2" drive torque wrench: Torque to 135 Nm (100 ft-lbs).

---

✅ After Repair

• Start the engine and watch the belt for 20–30 seconds; it should run smooth with no wandering.
• Listen for squeal, chirping, or grinding; if present, shut off and re-check belt seating and pulley condition.
• Take a short test drive, then re-check for any abnormal noise.

---

💰 DIY vs Shop Cost

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

DIY Cost: $25-$70 (parts only)

You Save: $155-$280 by doing it yourself!

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