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Gates 38781 Accessory Drive Belt Tensioner Assembly - Alternator - Right Side
OE Automatic Belt Tensioner for Hyundai and Kia
Gates DriveAlign Premium OE Automatic Belt Tensioner 38781 is built for accessory drive belt systems that need stable belt control and OE-style fit. It is a steel tensioner assembly with a smooth backside pulley and OE Exact comparison rating for direct replacement service.
Fits 2011-2016 Kia Optima, Alternator - Right Side. Fits 2011-2015 Hyundai Sonata, Alternator - Right Side.
Key Features
- Steel tensioner assembly for accessory drive belt system service
- DriveAlign Premium OE Automatic Belt Tensioner line from Gates
- OE Exact comparison rating for OE-style fit, form, and function
- Single pulley design with smooth/backside contact surface
- V-ribbed belt application
- Mounting hole quantity: 1
- Outside diameter: 65 mm; width: 29 mm
Detailed Description
Gates 38781 is an accessory drive belt tensioner assembly engineered to match original equipment specifications for the alternator drive on select Hyundai Sonata and Kia Optima applications. Gates applies OE system design experience to its DriveAlign Premium OE Automatic Belt Tensioner line, with manufacturing held to rigid tolerances for consistent fit and operation. The steel construction, smooth/backside pulley contact surface, and OE Exact rating support direct replacement on the right-side alternator drive setup.
This part cross-references Litens 999693A for the same application.
What This Part Helps Address
- Belt squeal caused by weak or inconsistent tension
- Accessory belt flutter on the alternator drive
- Uneven belt tracking on V-ribbed belt systems
- Noise from a worn tensioner pulley or bearing
- Loss of proper belt tension after component wear
Installation Notes and Tips
Verify the belt routing and confirm the alternator - right side application before installation. Inspect the accessory drive belt, pulley surfaces, and adjacent components for wear before replacing the tensioner. Confirm the mounting point and pulley alignment match the original unit on the vehicle.
Quality Assurance
Gates manufactures this DriveAlign tensioner to OE-level specifications and tight dimensional tolerances to support original-equipment fit and function on the listed Hyundai Sonata and Kia Optima applications.
| Brand | Gates |
|---|---|
| Part Number | 38781 |
| Position | DriveAlign Premium OE Automatic Belt Tensioner, Alternator - Right Side |
| Material | Steel |
| Pulley 1 Flanged | No |
| Bearing Bore Inside Diameter | .67 |
| Bearing Bore Inside Diameter | 17 |
| Width | 1.14 |
| Width | 29 |
| Outside Diameter | 2.56 |
| Outside Diameter | 65 |
| Mounting Hole Quantity | 1 |
| Belt Type | V-ribbed |
| Pulley Quantity | 1 |
| Contact Surface | Smooth/backside |
| Contents | Tensioner assy. |
| OE Comparison Rating | Oe exact |
This part fits 11 vehicles. Search below:
| Year | Make | Model | Liters | Cylinders | Fuel Type | Position | Notes |
|---|---|---|---|---|---|---|---|
| 2016 | Kia | Optima | 2.4L | L4 | FULL HYBRID EV-GAS (FHEV) | Alternator - Right Side | DriveAlign Premium OE Automatic Belt Tensioner |
| 2015 | Hyundai | Sonata | 2.4L | L4 | FULL HYBRID EV-GAS (FHEV) | Alternator - Right Side | DriveAlign Premium OE Automatic Belt Tensioner |
| 2015 | Kia | Optima | 2.4L | L4 | FULL HYBRID EV-GAS (FHEV) | Alternator - Right Side | DriveAlign Premium OE Automatic Belt Tensioner |
| 2014 | Hyundai | Sonata | 2.4L | L4 | FULL HYBRID EV-GAS (FHEV) | Alternator - Right Side | DriveAlign Premium OE Automatic Belt Tensioner |
| 2014 | Kia | Optima | 2.4L | L4 | FULL HYBRID EV-GAS (FHEV) | Alternator - Right Side | DriveAlign Premium OE Automatic Belt Tensioner |
| 2013 | Hyundai | Sonata | 2.4L | L4 | FULL HYBRID EV-GAS (FHEV) | Alternator - Right Side | DriveAlign Premium OE Automatic Belt Tensioner |
| 2013 | Kia | Optima | 2.4L | L4 | FULL HYBRID EV-GAS (FHEV) | Alternator - Right Side | DriveAlign Premium OE Automatic Belt Tensioner |
| 2012 | Hyundai | Sonata | 2.4L | L4 | FULL HYBRID EV-GAS (FHEV) | Alternator - Right Side | DriveAlign Premium OE Automatic Belt Tensioner |
| 2012 | Kia | Optima | 2.4L | L4 | FULL HYBRID EV-GAS (FHEV) | Alternator - Right Side | DriveAlign Premium OE Automatic Belt Tensioner |
| 2011 | Hyundai | Sonata | 2.4L | L4 | FULL HYBRID EV-GAS (FHEV) | Alternator - Right Side | DriveAlign Premium OE Automatic Belt Tensioner |
| 2011 | Kia | Optima | 2.4L | L4 | FULL HYBRID EV-GAS (FHEV) | Alternator - Right Side | DriveAlign Premium OE Automatic Belt Tensioner |
* Always verify fitment with your vehicle's VIN if unsure. Submodel & trim restrictions may apply.
This part directly replaces or is cross-referenced with the following part numbers:
Cross-reference numbers are provided for identification purposes only. Always confirm fitment before ordering.