2019 Subaru Crosstrek Serpentine Belt: Routing, Replacement, and Part Numbers

Quick Answer

• Belt Length: Varies by engine (see below)
• Rib Count: 6-rib
• OEM Belt PN:
  • 2.0L (FB20D engine): 809221150
• Aftermarket Cross-references:
  • Gates K060858 (for 2.0L)
  • Dayco 5060858 (for 2.0L)
  • Continental Elite 4060858 (for 2.0L)
• Auto-Tensioner PN:
  • 2.0L (FB20D engine): 23769AA01A
• Idler Pulley PN:
  • 2.0L (FB20D engine): 23770AA020

Belt Routing

The 2019 Subaru Crosstrek, equipped with the 2.0L FB20D engine, utilizes a single serpentine belt to drive all its accessories. Before you begin any work, it's highly recommended to take a clear photograph of your existing belt routing. This will serve as an invaluable reference during reinstallation.

Here's a step-by-step description of the routing path:

1. Crankshaft Pulley: Start at the lowest, largest pulley – the crankshaft pulley. The belt comes off the top.
2. A/C Compressor: From the crankshaft pulley, the belt travels upwards and slightly to the right (passenger side) to wrap around the air conditioning compressor pulley.
3. Idler Pulley: After exiting the A/C compressor, the belt continues upwards to engage with the smooth idler pulley, which helps guide the belt.
4. Alternator: The belt then goes from the idler pulley directly to the alternator pulley, typically located high on the driver's side of the engine.
5. Power Steering Pump: From the alternator, the belt goes downwards to the power steering pump pulley.
6. Water Pump: The belt then travels to the water pump pulley, usually located below or near the power steering pump.
7. Tensioner Pulley: Finally, the belt wraps around the auto-tensioner pulley, which provides the necessary tension to keep the belt snug and prevent slippage. The belt will feed from the tensioner back down to the crankshaft pulley to complete the loop.

How to Replace the Serpentine Belt

Replacing the serpentine belt on your 2019 Subaru Crosstrek is a manageable task for most DIYers, provided you have the right tools and a little patience. You will need a serpentine belt tool or a 3/8-inch breaker bar to release the tension on the auto-tensioner.

1. Safety First: Ensure the engine is cool and the vehicle is safely supported on jack stands if you need more room underneath.
2. Document Routing: As mentioned, take a photo of the current belt routing before removal.
3. Release Tension: Locate the auto-tensioner. Attach your serpentine belt tool or breaker bar to the square drive hole on the tensioner arm. Rotate the tool/bar clockwise (or counter-clockwise, depending on the tensioner's design – observe the tensioner's movement) to relieve the tension. While holding the tensioner in this position, carefully slip the belt off one of the easier pulleys, like the alternator or idler.
4. Remove Old Belt: Once the tension is released, completely remove the old belt from all pulleys.
5. Install New Belt: Route the new belt according to your photograph and the description above. Make sure the belt ribs align correctly with the ribbed pulleys and the back of the belt rides smoothly on the smooth idler pulley.
6. Tension Belt: Once the new belt is properly routed on all pulleys except for the final one (usually the tensioner or an idler to make it easier), use your tool to release the tensioner again. Slip the new belt onto the remaining pulley. Slowly release the tensioner, allowing it to apply proper tension to the new belt.
7. Double-Check: Visually inspect to ensure the belt is seated correctly on all pulleys and that no part of the belt is off-track.
8. Start Engine: Start the engine and listen for any unusual noises (squealing, chirping). Let it run for a minute or two, then shut it off and re-inspect the belt's position.

Replacement Interval

Subaru typically recommends inspecting the serpentine belt at every scheduled service interval (e.g., every 30,000 miles or 30 months) and replacing it as needed. There isn't a strict mileage-based replacement interval for the serpentine belt itself, as its lifespan can vary significantly based on driving conditions and engine bay temperatures. However, it's generally a good practice to consider replacement around 60,000 to 100,000 miles, or if you notice any of the