The 06A 903 315 (Gates 38018) is an OE-quality accessory drive belt idler pulley for select Volkswagen and Audi applications. Engineered to OE dimensions with a premium sealed bearing, this direct-fit pulley restores correct belt alignment and quiet, smooth accessory drive operation no modifications required.
$24.93
The 06A 903 315 Accessory Drive Belt Idler Pulley by Gates is an OE-quality replacement for select Volkswagen and Audi vehicles. The idler pulley guides the accessory drive (serpentine) belt through its routing path, maintaining proper belt alignment and load distribution across all belt-driven accessories — including the alternator and A/C compressor.
Because the idler pulley spins continuously at engine speed, its sealed bearing is subject to constant load, heat, and contamination over time. As the bearing wears, it generates chirping or grinding noise, allows pulley wobble, and causes belt flutter and uneven belt wear. Left unaddressed, a failing idler pulley accelerates belt wear and can lead to unexpected belt loss. Replacing the worn unit with this 06A 903 315 restores quiet, consistent belt tracking and long-term accessory drive reliability.
Gates is a globally recognized OE supplier of belt drive components trusted by major automotive manufacturers worldwide. The 06A 903 315 is manufactured to OE specifications, matching the original pulley profile and bearing dimensions exactly. Its premium sealed bearing delivers smooth, quiet rotation under continuous engine load, and the OE-spec pulley groove geometry ensures full belt contact and correct tracking alignment throughout the accessory drive circuit — a true direct-fit replacement requiring no modifications.
Catching idler pulley failure early prevents belt loss and accessory system damage. Look for the following symptoms:
Chirping, squealing, or grinding noise from the front of the engine that changes with engine speed
Visible pulley wobble or lateral movement when inspected at idle
Belt flutter, vibration, or inconsistent tracking across pulleys
Accelerated or uneven wear on the accessory drive belt
Roughness or resistance when spinning the pulley by hand with the engine off
If any of these indicators are present, the idler pulley should be replaced promptly.
OEM Reference: 06A 903 315D / 06A 903 315E / 06A 903 315F
Gates Part Number: 38018
Brand: Gates — globally trusted OE belt drive component supplier
Premium sealed bearing for smooth, quiet rotation under continuous load
OE-spec pulley profile for correct belt alignment and tracking
Heat- and vibration-resistant construction for long service life
Direct-fit replacement — no modifications required
Helps prevent belt squeal, flutter, and premature belt wear
Always inspect and replace the accessory drive belt if it shows cracking, glazing, or fraying — replacing both together ensures a complete service
Check the belt tensioner and all remaining pulleys for bearing noise, play, or rough rotation; replace any worn components at the same time
Verify correct belt routing before startup to ensure the belt is fully seated in all pulley grooves
Always verify fitment by VIN before ordering. Multiple variants may exist within the same model year.
06A 903 315D / 06A 903 315E / 06A 903 315F (OEM VAG)
Gates 38018
FEBI 30585 (shared application)
DORMAN 419-016
Continental Elite 49438
| Weight | 0.80 lbs |
|---|---|
| Dimensions | 5.0 × 5.0 × 2.0 in |
| Year | Make | Model | Engine | Notes |
|---|---|---|---|---|
| 2006-2008, 2010-2013 | Audi | A3 | ||
| 2009-2010 | Audi | A4 | ||
| 2010-2011 | Audi | A5 | ||
| 2000-2006, 2008 | Audi | TT | ||
| 2008 | BMW | 128i | ||
| 2007-2013 | BMW | 328i | ||
| 2007 | BMW | 525i | ||
| 2008 | BMW | 528i | ||
| 2007-2008 | BMW | X3 | ||
| 2000-2001, 2003 | BMW | X5 | ||
| 2006-2009 | BMW | Z4 | ||
| 1998-2005 | Volkswagen | Beetle | ||
| 2009 | Volkswagen | CC | ||
| 2008 | Volkswagen | EOS | ||
| 2006 | Volkswagen | GTI | ||
| 1999-2006, 2010, 2012, 2014 | Volkswagen | Golf | ||
| 2006-2008 | Volkswagen | Passat | 2.0L |
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