Silence belt squeal and keep every belt-driven accessory spinning with the INA US Accessory Drive Belt Tensioner Assembly (FT40121). It installs as a direct-fit replacement for the 2002-2005 BMW 745I and 745LI, 2003-2008 BMW 760LI, 2003-2006 BMW X5, 2004 BMW 645CI, 2004-2006 BMW 760I, and 2006-2010 BMW 550I.
This tensioner applies constant, controlled load to the accessory drive belt so it maintains grip on the crankshaft and the driven accessory pulleys across changing engine speeds.
- Automatic tensioning: holds proper belt tension to help reduce slip and squeal.
- Complete assembly: replaces the worn original as a single unit.
- Belt control: helps keep the accessory drive belt tracking correctly on the pulleys.
Signs the tensioner may need replacing include belt chirp or squeal, a rattle or knock from the tensioner area, belt slip, or visible belt wear. These symptoms can have other causes, so diagnose the source first; if a worn or noisy tensioner is the cause, this assembly replaces it.
Interchange: 11 28 7 505 566 · 11287505566 · 11 28 7 549 589 · 11287549589 · 7 505 566 · 7505566 · 7 549 589 · 7549589 · APV2304 · 55048 · 5340121100 · 10-0716 · 100716
Manufacturer part number FT40121.
This part cross-references / interchanges with the following part numbers:
11 28 7 505 566, 11 28 7 549 589, 7 505 566, 7 549 589, APV2304, 55048, 5340121100, 10-0716
