Fan Belt Replacement

Remove and replace the serpentine accessory drive belt on the 8.4L V10 engine, including tensioner inspection and belt routing verification.

Warnings

Tools required

Parts

• Serpentine belt × 1 — Gates K080950 or Mopar 5080950AA

Preparation

1. Ensure engine is completely cold to the touch
2. Park vehicle on level ground and engage parking brake
3. Open hood and secure with prop rod
4. Photograph or sketch the serpentine belt routing for reference before removal (routing diagram is also located on the fan shroud or underside of hood)

Procedure

1. 1

   Locate and inspect belt routing
   From the front of the engine, identify the serpentine belt path. The 8.4L V10 uses a single serpentine belt that routes around the crankshaft pulley, water pump, power steering pump, alternator, A/C compressor, and idler/tensioner pulleys. The automatic belt tensioner location should be identified from the belt routing diagram before proceeding. Verify the routing matches the diagram on the fan shroud before removal.
2. 2

   Release belt tension
   Insert a 1/2" drive breaker bar into the square drive on the belt tensioner arm. Rotate the tensioner in the direction that relieves tension on the belt (confirm direction against the tensioner arm travel). Hold the tensioner in the released position.
3. 3

   Remove serpentine belt
   While holding the tensioner in the released position, slip the belt off the nearest pulley (alternator or water pump recommended for easiest access). Carefully release the tensioner back to its resting position. Remove the belt completely from all pulleys and extract it from the engine bay.
4. 4

   Inspect tensioner and pulleys
   With the belt removed, rotate the tensioner pulley by hand and check for roughness, grinding, or excessive free play indicating bearing wear. Inspect the pulley face for cracks or glazing. Check that the tensioner arm moves smoothly through its full range and returns to the rest position with adequate spring pressure. Inspect all idler pulleys for similar wear indicators. Spin each pulley and listen for bearing noise.
5. 5

   Clean pulley surfaces
   Use a wire brush and shop towel to remove any rubber residue, dirt, or debris from all pulley grooves and faces. Pay particular attention to the crankshaft pulley, as debris here can cause belt tracking issues. Ensure all pulley surfaces are clean and smooth.
6. 6

   Route new belt
   Starting at the crankshaft pulley at the bottom of the engine, route the new serpentine belt around all pulleys except the tensioner pulley, following the diagram photographed earlier or the routing diagram on the fan shroud. Ensure the belt ribs are properly seated in each pulley groove. Leave the tensioner pulley for last.
7. 7

   Install belt on tensioner
   Using the 1/2" drive breaker bar in the tensioner arm square drive, rotate the tensioner in the release direction again. While holding the tensioner, slip the belt over the tensioner pulley, ensuring proper rib engagement. Slowly release the tensioner to apply proper tension to the belt. Remove the breaker bar.
8. 8

   Verify belt alignment and seating
   Visually inspect the entire belt path to confirm the belt is centered on all pulleys and fully seated in all grooves with no overlap or misalignment. The belt should track straight without riding to one side of any pulley. Correct any misalignment by repeating the installation process.
9. 9

   Perform test rotation
   Using a socket on the crankshaft bolt, manually rotate the engine clockwise through two complete revolutions. Watch the belt tracking on all pulleys during rotation. The belt should remain centered and properly seated throughout the full rotation without any jumping or misalignment.

Reassembly

1. No disassembly was required for this procedure beyond belt removal
2. Ensure all tools and materials are removed from engine bay before closing hood

Verification

• Start the engine and allow it to idle. Listen for any squealing, chirping, or abnormal noises from the belt area
• Visually confirm the belt is tracking properly on all pulleys at idle with no slippage or wobble
• Turn on accessories (A/C, power steering load) and verify belt operates smoothly under load without noise
• Recheck belt alignment after 5 minutes of operation and again after the first 50-100 miles of driving

More procedures for this vehicle