2020 Ford Transit Serpentine Belt: Routing, Replacement, and Part Numbers

Quick Answer

Engine: 3.5L EcoBoost V6

• Belt Length: 2375mm (93.5 inches)
• Rib Count: 6-rib
• OEM Belt PN: Ford JK2Z-8620-B (or equivalent GS7Z-8620-A or JK2Z-8620-A)
• Aftermarket Cross-references:
  • Gates K060935
  • Dayco 5060935
  • Continental Elite 4060935
• Auto-Tensioner PN: Ford CK4Z-6B209-E
  • Gates 38541
  • Dayco 89288
• Idler Pulley PN: Ford CK4Z-8678-A
  • Gates 36586
  • Dayco 89012

Engine: 3.2L Power Stroke I5 Diesel

• Belt Length: 2320mm (91.34 inches)
• Rib Count: 6-rib
• OEM Belt PN: Ford BK3Z-8620-A
• Aftermarket Cross-references:
  • Gates K060913
  • Dayco 5060913
  • Continental Elite 4060913
• Auto-Tensioner PN: Ford BK3Z-6B209-C
  • Gates 38539
  • Dayco 89286
• Idler Pulley PN: Ford BK3Z-8678-A
  • Gates 36402
  • Dayco 89037

Belt Routing

Important: Before attempting any belt removal, take a clear photo of your current serpentine belt routing. This will be an invaluable reference during reinstallation.

The 2020 Ford Transit may come with different engine options, and the belt routing will vary accordingly. Always verify your specific engine.

For 3.5L EcoBoost V6:

1. Begin at the crankshaft pulley (the largest pulley at the bottom, directly driven by the engine).
2. From the crankshaft, the belt typically travels upward to the A/C compressor pulley.
3. From the A/C compressor, the belt routes over the top of an idler pulley (a smooth pulley that guides the belt).
4. Next, the belt goes down and around the alternator pulley (powers the electrical system).
5. From the alternator, it typically goes up and around the power steering pump pulley (if equipped; assists steering).
6. From the power steering pump, the belt often routes to the water pump pulley (circulates coolant).
7. Finally, the belt runs around the serpentine belt tensioner pulley (provides constant tension) before returning to the crankshaft pulley, completing the loop.

For 3.2L Power Stroke I5 Diesel:

1. Start at the crankshaft pulley (the largest pulley at the bottom).
2. From the crankshaft, the belt ascends to the A/C compressor pulley.
3. After the A/C compressor, the belt often wraps under an idler pulley.
4. It then proceeds up to the alternator pulley.
5. From the alternator, the belt typically goes to the power steering pump pulley.
6. Next, it often rides over another idler pulley (or a combination of guide pulleys, depending on specific configuration).
7. The belt then goes down to the water pump pulley.
8. Finally, it loops around the serpentine belt tensioner pulley before heading back to the crankshaft.

How to Replace the Serpentine Belt

Replacing the serpentine belt on your 2020 Ford Transit requires a few basic tools and careful attention to detail:

1. Safety First: Ensure the engine is off and cool. Disconnect the negative battery terminal.
2. Locate the Tensioner: Identify the automatic serpentine belt tensioner. It will have a square opening, typically 3/8" or 1/2", designed to accept a breaker bar or a specialized serpentine belt tool.
3. Relieve Tension: Insert your breaker bar or serpentine belt tool into the square opening on the tensioner. Apply steady pressure in the direction that releases the belt tension (this usually means rotating it clockwise or counter-clockwise, depending on the engine configuration – observe the tensioner’s movement).
4. Remove Old Belt: While holding tension, slip the old belt off one of the easier pulleys (like a smooth idler). Once it's off a pulley, you can slowly release the tensioner and fully remove the old belt.
5. Route New Belt: Carefully route the new belt according to the diagram you photographed or the description above. This is the most critical step. Ensure the belt is properly seated in all pulley grooves.
6. Apply Tension & Final Seat: Once the belt is mostly routed, again apply pressure to the tensioner with your tool. Slip the belt over the last pulley. Double-check that all ribs are correctly seated in all grooves on every pulley.
7. Release Tensioner: Slowly release the tensioner, allowing it to apply proper tension to the new belt.
8. Final Inspection: Give the belt a visual check to ensure it's correctly aligned on all pulleys. Start the engine briefly (after reconnecting the battery) and listen for any abnormal noises or wobbles. Turn off the engine and re-check the belt.

Replacement Interval

Ford generally recommends inspecting the serpentine belt at every scheduled service interval and replacing it if signs of wear are present. As a proactive measure, many technicians recommend replacing the serpentine belt every 60,000 to 100,000 miles, or every 5-7 years, whichever comes first. However, driving conditions and environmental factors can influence this. It's always best to consult your owner's manual for the most accurate manufacturer recommendations for your specific 2020 Ford Transit model and engine.

Signs of a Failing Belt or Tensioner

Ignoring a failing serpentine belt or tensioner can lead to significant issues, including loss of power steering, A/C, alternator charging, and engine overheating. Look out for these warning signs:

• Squealing or Chirping Noises: This is the most common sign. A persistent squeal, especially on cold start or when turning the steering wheel (for power steering), often indicates a worn belt, misaligned belt, or a failing tensioner or pulley bearing.
• Cracks, Fraying, or Glazing on the Belt: Visually inspect the belt. Deep cracks, missing chunks, fraying edges, or a smooth, shiny (glazed) appearance on the ribbed side are all indicators that the belt needs replacement.
• Loss of Power Steering, A/C, or Charging: If your power steering becomes heavy, the A/C stops blowing cold, or the battery light illuminates on your dash, the serpentine belt may have broken or slipped off.
• Engine Overheating: A broken serpentine belt will stop the water pump from circulating coolant, leading to rapid engine overheating.
• Belt Wobble or Unusual Vibrations: If you notice the belt wobbling excessively while the engine is running, or if there are unusual vibrations coming from the belt system, it could point to a failing tensioner or a worn pulley bearing.
• Visible Wear on Tensioner or Idler Pulleys: Check the tensioner and idler pulleys for excessive play, grinding noises when spun by hand (when the belt is off), or signs of lubricant leakage.

Find a trusted shop on Repairius.