2023 Ford F-350 Super Duty Serpentine Belt Routing & Part Numbers

Quick Answer

The 2023 Ford F-350 Super Duty commonly uses two different serpentine belt systems depending on the engine. For the prevalent 6.7L Power Stroke Diesel engine, here are common specifications:

• Belt Length: Approximately 2665mm (104.9 inches)
• Rib Count: 8-rib
• OEM Belt PN (6.7L Power Stroke): FC3Z-8620-B (Motorcraft JK8-1049-B)
• Aftermarket Cross-references:
  • Gates K081049
  • Dayco 5081050
  • Continental Elite 4081050
• Auto-Tensioner PN (6.7L Power Stroke): HC3Z-6B209-A (Motorcraft JT1024)
• Idler Pulley PN (6.7L Power Stroke, common): BC3Z-6C348-A (Motorcraft YS369)

(Note: Always verify part numbers with your VIN for exact fitment, especially with different engine options like the 7.3L Godzilla gas engine.)

Belt Routing (6.7L Power Stroke Diesel)

Before attempting any belt removal, it is highly recommended to take a clear photograph of the existing belt routing. This will serve as an invaluable guide during reinstallation. The 6.7L Power Stroke engine in your 2023 F-350 Super Duty features a comprehensive serpentine belt system. Follow this path for proper routing:

1. Crankshaft Pulley: Begin at the largest pulley at the bottom, which is the crankshaft pulley. The belt comes off the top passenger side of this pulley.
2. A/C Compressor: From the crankshaft, the belt travels upward and engages the smooth top of the A/C compressor pulley.
3. Idler Pulley (lower-passenger side): After the A/C compressor, the belt goes directly to a smooth idler pulley located lower on the passenger side.
4. Alternator: From this idler, the belt loops up and over the ribbed pulley of the alternator, typically positioned high on the passenger side.
5. Power Steering Pump: The belt then deviates towards the front of the engine, wrapping around the ribbed power steering pump pulley, usually found above the passenger-side frame rail.
6. Water Pump: Next, the belt goes around the ribbed water pump pulley, often centrally located higher up on the front of the engine.
7. Tensioner: Finally, the belt routes around the serpentine belt tensioner pulley, which is typically found near the top-center or slightly to the driver's side, before returning to the crankshaft pulley. The ribbed side of the belt will ride in the grooves of these components.

How to Replace the Serpentine Belt

Replacing the serpentine belt on your F-350 requires a few basic tools and a bit of mechanical know-how.

1. Safety First: Ensure the engine is off and cool. Disconnect the negative battery terminal to prevent accidental starting.
2. Locate the Tensioner: Identify the automatic belt tensioner. It will have a square drive hole (often 3/8-inch or 1/2-inch) or a hex bolt in its arm.
3. Relieve Tension: Insert a serpentine belt tool or a long breaker bar/ratchet into the square drive hole (or use a wrench on the hex bolt). Rotate the tool clockwise or counter-clockwise (depending on the tensioner design) to pivot the tensioner arm and loosen the belt tension.
4. Remove the Old Belt: While holding the tensioner open, carefully slip the old belt off one of the pulleys (e.g., the alternator or idler pulley).
5. Inspect Pulleys: With the belt off, take this opportunity to manually spin each pulley (alternator, A/C compressor, power steering, idlers). Listen for grinding noises and check for excessive wobble, which could indicate a failing bearing. Also, inspect the tensioner pulley itself.
6. Route the New Belt: Following your previously taken photograph or the routing description above, carefully route the new belt around all the pulleys, leaving one pulley (like the alternator or idler) free.
7. Final Tensioning: Once the belt is mostly in place, use your serpentine belt tool or breaker bar to again pivot the tensioner arm, creating enough slack to slip the new belt over the final pulley. Ensure the belt is properly seated in all the grooves.
8. Verify & Test: Slowly release the tensioner. Double-check that the belt is correctly aligned on all pulleys. Start the engine briefly and observe the belt for any unusual wobbling or noise. Turn off the engine and recheck alignment.

Replacement Interval

Ford generally recommends inspecting the serpentine belt at every oil change or major service interval (e.g., every 10,000 to 15,000 miles). While many modern serpentine belts can last 60,000 to 100,000 miles, factors like extreme temperatures, contamination (oil, coolant), and heavy loads can shorten their lifespan. It's prudent to consider replacement around the 60,000 to 75,000-mile mark, or sooner if signs of wear are present.

Signs of a Failing Belt or Tensioner

A failing serpentine belt or tensioner can lead to a loss of power to critical accessories and eventually leave you stranded. Be aware of these warning signs:

• Squealing or Chirping Noises: This is one of the most common indicators. A worn or misaligned belt, or a failing pulley bearing (including the tensioner and idlers), can cause these sounds, especially on cold starts or when the engine is under load.
• Cracks, Fraying, or Glazing on the Belt: Visually inspect the belt. Cracks on the ribbed side, frayed edges, missing chunks, or a shiny, glazed appearance on either side are all signs that the belt is degrading and should be replaced.
• Loss of Power Steering: If your power steering suddenly becomes difficult, especially at low speeds, it could mean the belt is slipping or has broken.
• Overheating Engine: A broken belt will stop the water pump from circulating coolant, leading to rapid engine overheating.
• Dim or Flickering Lights/Battery Light On: A failing or broken belt will stop the alternator from charging the battery, leading to electrical issues and eventually a dead battery.
• A/C Not Working: The A/C compressor relies on the serpentine belt. If your A/C stops blowing cold, the belt could be at fault.
• Tensioner Play or Noise: With the engine off, visually inspect the tensioner. It should hold the belt firmly. Excessive vibration, wobble, or a noticeable "thunking" noise coming from the tensioner (sometimes only audible when the engine is running) can indicate a failing tensioner bearing or spring.

Address these symptoms promptly to avoid more significant issues on the road.

Find a trusted shop on Repairius.