Original BMW Accessory Belt Deflection Pulley for BMW X5 xDrive35d (2009–2013)

This Original BMW deflection pulley is the idler that guides the accessory drive belt on the M57N2 diesel six-cylinder in the 2009–2013 BMW X5 xDrive35d. It works with the belt tensioner to keep tension on the belt, and it sets the belt's path around engine-driven accessories such as the power steering pump, water pump, A/C compressor, and alternator. BMW's parts data places this pulley on the E70 X5 diesel range, both before and after the facelift. BMW's parts data lists this part number in production since January 2019. Each pulley is made in France.

Original BMW Parts carry a 24-month parts warranty.

An idler pulley has no adjustment of its own. It spins on an internal bearing and only redirects the belt, while the tensioner supplies the spring load. Because it runs whenever the engine runs, the idler is easy to overlook during belt service even though it matters as much as the tensioner. Outside North America, BMW fits the same deflection pulley to the E70 3.0d, 3.0sd, and 3.5d, which all share the M57N2 engine with the U.S. xDrive35d.

Technical Details

• Manufacturer: BMW, sold as an Original BMW part
• Part number: 11-28-8-585-243
• BMW part name: deflection pulley
• Function: accessory drive belt idler pulley
• Engine: M57N2 diesel six-cylinder
• Chassis: E70 X5 and E70 facelift
• Production start: January 2019
• Country of manufacture: France
• Sold individually, one pulley per order
• Warranty: 24-month Original BMW parts warranty

Installation & Tuning Notes

In most cases, the idler pulley should be replaced at the same time as the belt tensioner. Check whether the old pulley sits out of line with its mounting surface, and replace it together with the belt tensioner.

Common Questions

How do I know the deflection pulley is worn?
Watch for visible wear or grooves on the pulley, belt squealing, and chirping or grinding from the bearing. Odd or uneven belt wear and a pulley that sits out of line with its mounting surface also point to the idler.

Will this fit a gasoline X5?
No. BMW applies it to the M57N2 diesel in the E70, which in the U.S. is the xDrive35d.

Fitment & Compatibility

Check the table below for the exact year, model, submodel, and any listed notes. With over 20 years of parts and fitment experience, PMB Performance can match this to your VIN.