Dayco E040318 Serpentine Belt - Air Conditioning

Dayco E040318 Serpentine Belt for Subaru A/C

Dayco E040318 is a black EPDM4 serpentine belt for the accessory drive belt system, built for Subaru air conditioning applications. It is an elastic self-tensioning belt used on select Subaru WRX STI, WRX, Impreza, Forester, and Outback models, with fitment that spans 2008-2021 depending on vehicle and configuration.

Key Features

• EPDM4 construction for durable belt performance
• 4-rib, K-section profile with straight rib design
• Black finish with a .54 in top width
• Free length: 31.8 in / 807.720 mm
• Built to SAE J1459 standards
• Operating temperature range: -45°F to 212°F
• Subaru air conditioning belt application

Product Details

This Dayco serpentine belt is specified for Subaru air conditioning drive use and is listed for 2021 Subaru WRX STI, 2013-2020 Subaru WRX STI, 2008-2014 Subaru Impreza, 2013-2014 Subaru WRX, 2009-2013 Subaru Forester, 2009-2011 Subaru Outback, and 2008 Subaru Outback. The Dayco E040318 part number is associated with an elastic self-tensioning belt design, so correct application and proper installation procedure matter for belt alignment and tension control. This part cross-references Gates K040317SF and Subaru 11718-AA082 for the same application.

What It Helps Address

• Squealing or slipping accessory drive belt noise
• Cracked, glazed, or worn A/C belt surfaces
• Loss of proper drive to the air conditioning compressor
• Belt fitment issues on Subaru elastic self-tensioning applications
• Service replacement for aging Subaru WRX STI, WRX, Impreza, Forester, and Outback belts

Installation Notes and Tips

Installation tool 93878 is required for the listed Subaru elastic self-tensioning applications. Verify the vehicle year, model, and A/C belt routing before installation, and confirm the belt matches the specified 4-rib K-section profile and 31.8-inch free length. For Subaru WRX STI, WRX, Impreza, Forester, and Outback fitments, follow the service procedure for elastic belts to avoid damage during installation.

Quality Assurance

Dayco manufactures this belt to SAE J1459 standards and uses EPDM4 material for temperature resistance and belt durability across a wide operating range. The product line note indicates this part is superseded by 4PK828EE and is available until depleted. Part number E040318 remains the reference for this listing.