Gates 39477 Accessory Drive Belt Tensioner Assembly

OE Automatic Belt Tensioner for Subaru Applications

The Gates DriveAlign Premium OE Automatic Belt Tensioner, part number 39477, is built for Subaru accessory drive belt systems that require precise belt control and stable pulley alignment. It is an OE Exact replacement made to match factory fit, form, and function for a direct-service repair.

Compatible with Subaru Ascent, Crosstrek, Forester, Impreza, Legacy, Outback, WRX, XV, and XV Crosstrek applications, this tensioner supports consistent belt tension in V-ribbed accessory drive systems. Gates 39477 is engineered for OE-style service on vehicles that need accurate belt tracking and dependable pulley operation.

Key Features

• DriveAlign Premium OE Automatic Belt Tensioner assembly
• OE Exact grade for factory-style replacement fitment
• Thermoplastic housing for application-specific durability
• Single smooth/backside pulley with no grooves
• V-ribbed belt system application
• Two mounting holes for direct installation alignment
• Designed to match OE dimensions and specifications

Product Details

Gates 39477 is an accessory drive belt tensioner assembly developed from Gates OE system design experience. The tensioner uses a thermoplastic body, a 2.76-inch (70 mm) outside diameter pulley, and a 1-inch (25.5 mm) pulley width with a 17 mm bearing bore inside diameter. Its smooth pulley profile is suited to backside belt contact in V-ribbed accessory drive layouts, helping maintain proper belt routing and tension control.

This part cross-references Four Seasons 39477 for the same application. It is a direct replacement choice for Subaru owners searching for a Subaru Ascent belt tensioner, Subaru Crosstrek automatic belt tensioner, or Subaru Outback accessory drive belt tensioner, and it also serves Subaru Forester, Impreza, Legacy, WRX, XV, and XV Crosstrek fitments listed below.

What It Helps Address

• Belt squeal caused by weak or inconsistent tension
• Accessory drive belt flutter or poor tracking
• Noise from a worn tensioner pulley or bearing
• Reduced belt control in the accessory drive system
• Factory-style replacement needs for Subaru belt service

Installation Notes and Tips

Verify belt routing, pulley alignment, and mounting-hole alignment before installation. Inspect the accessory drive belt, idler pulleys, and adjacent components for wear before replacing the tensioner. Confirm the vehicle application by year and model, especially on Subaru Ascent, Crosstrek, Forester, Impreza, Legacy, Outback, WRX, XV, and XV Crosstrek fitments.

• Fits 2019-2025 Subaru Ascent, N/A
• Fits 2018-2025 Subaru Crosstrek, N/A
• Fits 2016 Subaru Crosstrek, N/A
• Fits 2025 Subaru Forester, N/A
• Fits 2017-2025 Subaru Impreza, N/A
• Fits 2020-2025 Subaru Legacy, N/A
• Fits 2020-2025 Subaru Outback, N/A
• Fits 2022-2025 Subaru WRX, N/A
• Fits 2018-2020 Subaru XV, N/A
• Fits 2015 Subaru XV Crosstrek, N/A

Quality Assurance

Gates applies OE system design standards and rigid manufacturing tolerances to help ensure OE fit, form, and function. The DriveAlign Premium OE Automatic Belt Tensioner line is built to meet the specifications expected in factory-style Subaru accessory drive belt service.