Mercedes Sprinter Idler Pulley – INA | NCV3 3.0L OM642 | #6261500060 (2007–2018)

A worn or seized idler pulley on a Sprinter OM642 creates a persistent squealing or grinding noise from the front of the engine and — if allowed to seize completely — stops the serpentine belt and shuts down the alternator, power steering, and A/C simultaneously. This is the INA idler pulley for NCV3 Sprinters equipped with the 3.0L OM642 diesel engine, a direct replacement that restores smooth, noise-free belt routing.

What This Part Does

The idler pulley is a sealed bearing assembly with a smooth outer race that the serpentine belt wraps around to change direction and maintain the correct routing geometry across all driven accessories. The OM642's serpentine belt system uses one or more idler pulleys to guide the belt from the crankshaft pulley to the alternator, power steering pump, and A/C compressor at the correct approach and wrap angles. The idler's sealed ball bearing must spin freely and quietly under continuous belt tension and the heat of the engine bay environment. When the bearing's grease breaks down, its races develop wear or pitting, or it develops slight misalignment from bracket wear, the bearing begins to produce a squeal or grinding that progressively worsens until the bearing seizes.

Common Symptoms of a Failing Idler Pulley

• Squealing or chirping from the front of the engine that changes with engine speed
• Grinding or rumbling from the belt area that worsens under accessory load
• Belt jumping or vibrating from an idler with bearing play
• Serpentine belt wear that is uneven or accelerated from misaligned pulley
• Bearing wobble or roughness confirmed when the pulley is spun by hand with the belt removed

When to Replace

Replace when bearing noise is confirmed to the idler pulley, or during any serpentine belt service — the idler's service life parallels the belt, and replacing the belt alone on a worn idler will produce immediate noise and accelerated belt wear. Always replace idler pulleys and belt tensioners together as a matched set.

NCV3 OM642 Specific — VIN Verification Required

This idler pulley is for NCV3 Sprinters equipped with the 3.0L OM642 diesel engine. Always verify your engine code and VIN before ordering. Contact us and we'll confirm fitment before you buy.

Fitment

• 2007–2018 Mercedes-Benz Sprinter 2500 / 3500 – 3.0L OM642 (NCV3/W906)
• 2007–2009 Dodge Sprinter 2500 / 3500 – 3.0L OM642 (NCV3)
• 2007–2018 Freightliner Sprinter 2500 / 3500 – 3.0L OM642 (NCV3)

✔ Always replace belt tensioner and serpentine belt at the same service

Part Numbers

• Mercedes OEM: 6261500060 / A6261500060 / 626-150-00-60
• Manufacturer: INA — 15-3413 / 29709
• SKU: 6261500060