This procedure covers the removal and replacement of the alternator on a 2015-2020 Ford F-150 with the 5.0L Coyote V8 engine, including serpentine belt removal and electrical connections.

Warnings

Tools required

Parts

• Alternator × 1 — OEM Ford GL3Z-10346-B or equivalent 220A alternator
• Serpentine belt × 1 — Replace if worn, cracked, or glazed

Preparation

1. Park vehicle on level ground and engage parking brake
2. Turn ignition off and remove key from vehicle
3. Open hood and secure with prop rod
4. Allow engine to cool completely if recently operated
5. Locate alternator on passenger side of engine, mid-height position

Procedure

1. 1

   Disconnect battery negative terminal
   Using a 10mm socket, loosen the negative battery terminal bolt. Remove the negative cable from the battery post and secure it away from the terminal to prevent accidental reconnection. Wait at least 2 minutes for system capacitors to discharge.
   Torque spec

   Battery Terminal Bolts8 Nm (6 lb-ft)
2. 2

   Document and remove serpentine belt
   Take a clear photo of the serpentine belt routing for reference. Locate the spring-loaded tensioner pulley on the passenger side front of the engine. Using a 1/2" breaker bar or serpentine belt tool, rotate the tensioner clockwise to release tension. Slip the belt off one pulley, then slowly release tensioner. Remove belt from remaining pulleys and extract from engine bay.
3. 3

   Disconnect alternator electrical connections
   Locate the plastic connector on the back of the alternator and press the release tab while pulling the connector straight off. Identify the B+ power cable with rubber boot on the alternator stud. Pull back the rubber boot, then use a 10mm socket to remove the nut securing the power cable to the B+ terminal. Carefully lift the cable off the stud and secure it away from the alternator.
   ⚠Do not allow the B+ cable to contact ground or other metal surfaces. Although battery is disconnected, residual charge may be present.
4. 4

   Remove upper alternator mounting bolt
   Using a 15mm socket, remove the upper alternator mounting bolt that passes through the alternator ear into the mounting bracket. This bolt is accessible from above. Keep this bolt and any washers together for reinstallation.
   Torque spec

   Alternator Mounting Bolts50 Nm (37 lb-ft)
5. 5

   Remove lower alternator pivot bolt
   Access the lower pivot bolt at the bottom of the alternator. This may require reaching down from above or accessing from below depending on your reach. Using a 15mm socket, remove the pivot bolt. The alternator should now be free to remove.
   Torque spec

   Alternator Pivot Bolt25 Nm (18 lb-ft)
6. 6

   Remove alternator from vehicle
   Carefully maneuver the alternator out of the engine bay. You may need to tilt it at an angle to clear the engine block and other components. Lift it up and out through the top of the engine bay. Be careful not to drop the unit as it is heavy.
7. 7

   Inspect mounting surfaces and clean connections
   Inspect the alternator mounting bracket for cracks or damage. Use a wire brush to clean the mounting bolt holes and surfaces of any corrosion or debris. Check the ground contact point on the mounting bracket and clean if necessary. Inspect the serpentine belt for cracks, glazing, or excessive wear and replace if needed.
8. 8

   Install replacement alternator
   Position the new alternator into the mounting bracket, tilting as necessary to clear surrounding components. Align the lower pivot hole first, then align the upper mounting hole. Insert the lower pivot bolt finger-tight but do not fully tighten yet.
9. 9

   Secure alternator mounting bolts
   Install the upper alternator mounting bolt and tighten finger-tight. Using a torque wrench and 15mm socket, torque the upper mounting bolt to specification first. Then torque the lower pivot bolt to its specified torque value. Ensure the alternator is firmly seated and does not move in the bracket.
   Torque spec

   Alternator Mounting Bolts50 Nm (37 lb-ft)

   Alternator Pivot Bolt25 Nm (18 lb-ft)
10. 10

    Reconnect alternator electrical connections
    Position the B+ power cable over the terminal stud on the back of the alternator. Install the nut and tighten to the specified torque using a 10mm socket and torque wrench. Slide the rubber boot back over the connection. Push the electrical connector onto the alternator until it clicks into place, ensuring it is fully seated.
11. 11

    Install serpentine belt
    Reference your routing photo or the belt routing diagram on the radiator support. Route the belt around all pulleys except one that is accessible under the tensioner. Using a breaker bar, rotate the tensioner clockwise and slip the belt onto the final pulley. Slowly release the tensioner, ensuring the belt is properly seated in all pulley grooves.
    ⚠Verify the belt is properly seated in all pulley grooves before releasing tensioner. A misaligned belt can come off during operation or cause damage.
12. 12

    Reconnect battery negative terminal
    Clean the battery post and cable terminal with a wire brush if corrosion is present. Place the negative cable terminal onto the battery post and tighten the bolt to specification using a 10mm socket and torque wrench. Ensure the connection is secure.
    Torque spec

    Battery Terminal Bolts8 Nm (6 lb-ft)

Reassembly

1. Verify all electrical connections are secure and properly seated
2. Confirm serpentine belt is properly routed and seated in all pulley grooves
3. Ensure no tools or parts are left in the engine bay

Verification

• Start the engine and verify it runs smoothly without unusual noises from the alternator or belt area
• Check that the battery warning light on the instrument cluster illuminates briefly at key-on and then extinguishes after engine start
• Using a multimeter, verify charging voltage at battery terminals reads 13.8-14.4 volts with engine running at idle
• Turn on electrical accessories (headlights, HVAC blower, radio) and verify voltage remains within charging range
• Listen for proper belt operation with no squealing or chirping noises
• Inspect belt alignment visually to ensure it tracks properly on all pulleys
• Rev engine to 2000 RPM briefly and verify no belt slippage or abnormal noises occur

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