2024 Subaru Outback Serpentine Belt: Routing, Replacement, & Part Numbers

Quick Answer

The 2024 Subaru Outback, regardless of engine option (2.5L naturally aspirated or 2.4L turbocharged), utilizes a single serpentine belt to drive all accessories.

• Belt Length: Approximately 98.7 inches (2507 mm)
• Rib Count: 6-rib
• OEM Belt PN: 809221160
• Aftermarket Cross-references:
  • Gates K060987
  • Dayco 5060987
  • Continental Elite 4060987
• Auto-Tensioner PN: 23760AA070
• Idler Pulley PN: 23770AA020

Belt Routing

Before you begin any work, always take a clear photograph of your existing belt routing! This will be an invaluable reference when installing the new belt.

The serpentine belt on your 2024 Subaru Outback follows a specific path to drive various components. Here is a step-by-step description of the routing:

1. Begin at the Crankshaft Pulley (the lowest, largest pulley in the center, directly driven by the engine).
2. From the crankshaft, the belt travels up and to the right to the A/C Compressor Pulley (located on the lower passenger side of the engine).
3. From the A/C compressor, the belt continues up and to the left to the Idler Pulley (a smooth, often plastic or metal pulley that guides the belt, typically positioned above the A/C compressor).
4. The belt then travels upward from the idler pulley to the Alternator Pulley (located on the upper passenger side of the engine, often chrome or metallic silver).
5. From the alternator, the belt goes across the top of the engine to the Power Steering Pump Pulley (on the upper driver's side, if equipped with hydraulic power steering; otherwise, this pulley may be absent or replaced by an electric power steering system).
6. Next, the belt wraps downward and to the right around the Water Pump Pulley (typically located below the power steering pump, near the center of the engine).
7. Finally, the belt makes its way downward and to the left to the Automatic Belt Tensioner (a spring-loaded pulley system, usually with a visible arm, located on the lower driver's side, which maintains proper belt tension).

How to Replace the Serpentine Belt

Replacing the serpentine belt is a job many DIYers can tackle. You will need a serpentine belt tool or a long 3/8-inch drive breaker bar to release tension on the automatic tensioner.

1. Safety First: Ensure the engine is off and cool. Disconnect the negative terminal of the battery for added safety.
2. Document Routing: Take several clear photos of your current belt routing from different angles.
3. Release Tension: Locate the automatic belt tensioner. Insert your serpentine belt tool or breaker bar into the square hole on the tensioner arm. Rotate the arm clockwise (or counter-clockwise, depending on the tensioner design – observe which way it compresses) to relieve tension on the belt.
4. Remove Old Belt: While holding the tensioner open, carefully slip the old belt off one of the pulleys.
5. Inspect Pulleys: Once the old belt is removed, inspect all pulleys for wear, damage, or excessive play. Spin each pulley by hand; they should spin freely with no grinding noises. Check for oil leaks from any components.
6. Route New Belt: Using your photos as a guide, route the new belt around all pulleys, leaving the tensioner pulley for last. Double-check that all ribs are correctly seated in the pulley grooves.
7. Release Tensioner and Verify: Once the belt is mostly in place, re-apply tension with your tool, slip the belt over the tensioner pulley, and slowly release the tensioner. Ensure the belt is properly seated on all pulleys.
8. Re-connect Battery and Test: Reconnect the battery. Start the engine and let it run for a minute, visually checking the belt for proper alignment and listening for any unusual noises.

Replacement Interval

Subaru typically recommends inspecting the serpentine belt at every oil change or major service interval (e.g., every 15,000 miles / 24,000 km) and replacing it if signs of wear are present. Generally, a serpentine belt can last anywhere from 60,000 to 100,000 miles (96,000 to 160,000 km), but this can vary greatly depending on driving conditions and engine bay temperatures. Always refer to your 2024 Subaru Outback owner's manual for the most accurate maintenance schedule.

Signs of a Failing Belt or Tensioner

Don't wait for a complete belt failure, which can leave you stranded. Be alert for these warning signs:

• Squealing or Chirping Noises: This is the most common sign. It often indicates a loose or worn belt, or misaligned/failing pulley.
• Cracks, Fraying, or Glazing: Visually inspect the belt. Deep cracks, frayed edges, or a shiny, glazed appearance on the underside are clear signs of wear.
• Loss of Power Steering, A/C, or Charging: If the belt breaks or slips significantly, you will immediately lose power to the accessories it drives. Your power steering will become very stiff, the air conditioning will stop blowing cold, and your battery light may illuminate as the alternator stops charging.
• Thumping or Rattling from the Tensioner: A failing automatic tensioner can cause a noticeable thumping or rattling noise, especially at idle. The tensioner may also appear to vibrate excessively.
• Groove Wear on the Belt: If the ridges of the belt appear worn down or uneven, it's time for a replacement.

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