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BMW 645Ci Belt Tensioner

3 items

Find an A-Premium belt tensioner for squealing, slipping or uneven belt wear. Browse drive belt tensioners and pulley assemblies for your vehicle.

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Belt Tensioner for BMW 545i 550i 645Ci 650i 745i 745Li 750i 750Li 760iBelt Tensioner for BMW 545i 550i 645Ci 650i 745i 745Li 750i 750Li 760i
A-Premium®Part # APBT0131
Belt Tensioner for BMW 545i 550i 645Ci 650i 745i 745Li 750i 750Li 760i
4.6174 Reviews
$35.99
Low stock: Only 4 left
Edit ZIP code
3-year warranty
90 days free return
Fits 2007 - 2008 BMW Alpina B7, 2006 - 2010 BMW 550i, 2006 - 2010 BMW 650i, 2006 - 2008 BMW 750i, 2006 - 2008 BMW 750Li, 2004 - 2006 BMW 760i, 2004 - 2006 BMW X5, 2004 - 2006 BMW X5, 2004 - 2005 BMW 545i, 2004 - 2005 BMW 645Ci, 2003 - 2008 BMW 760Li, 2002 - 2005 BMW 745i, 2002 - 2005 BMW 745Li
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: BMW 645Ci
Item LocatedUnited States
Quantity1
Part interchange
11287549588, 11287505224, 11287542680
ConditionNew
item #10037Q30
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Drive Belt Tensioner Assembly for BMW X5 545i 550i 745i 750i 760i 745Li
AisinPart # BTBM-00072
Drive Belt Tensioner Assembly for BMW X5 545i 550i 745i 750i 760i 745Li
4.6174 Reviews
$51.99
Low stock: Only 4 left
Edit ZIP code
3-year warranty
90 days free return
Fits 2007 - 2008 BMW Alpina B7, 2006 - 2010 BMW 550i, 2006 - 2010 BMW 650i, 2006 - 2008 BMW 750i, 2006 - 2008 BMW 750Li, 2004 - 2006 BMW 760i, 2004 - 2006 BMW X5, 2004 - 2005 BMW 545i, 2004 - 2005 BMW 645Ci, 2003 - 2008 BMW 760Li, 2002 - 2005 BMW 745i, 2002 - 2005 BMW 745Li
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: BMW 645Ci
Item LocatedUnited States
Part interchange
366510358298
ConditionNew
item #1018ZX79
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ÜRO Parts 11287549588 Accessory Drive Belt Tensioner, Alternator and Water Pump
ÜRO PartsPart # 11287549588
ÜRO Parts 11287549588 Accessory Drive Belt Tensioner, Alternator and Water Pump
52 Reviews
$65.99
Edit ZIP code
3-year warranty
90 days free return
Fits 2007-2008 BMW Alpina B7, 2006-2010 BMW 550i, 2006-2010 BMW 650i, 2006-2008 BMW 750i, 2006-2008 BMW 750Li, 2004-2012 Rolls-Royce Phantom, 2004-2006 BMW 760i, 2004-2006 BMW X5, 2004-2006 BMW X5, 2004-2005 BMW 545i, 2004-2005 BMW 645Ci, 2003-2008 BMW 760Li, 2002-2005 BMW 745i, 2002-2005 BMW 745Li
Add Trim and Engine info to ensure a guaranteed fit
Vehicle: BMW 645Ci
Item LocatedUnited States
Quantity1
Installation PositionAlternator and Water Pump
ColorBlack
item #1000ZGS1
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What does a belt tensioner do?

Seat belt tensioners represent an integral facet of contemporary automotive safety systems. These sophisticated devices are meticulously engineered to augment passenger protection by mitigating the potentially injurious effects of a vehicular collision or abrupt deceleration event. 

Belt tensioner noise

Belt tensioner noise is typically an indication of a problem within the engine's accessory drive system, and it should not be ignored.

Squealing or Whining Noise: A common sign of a failing or worn-out belt tensioner is a high-pitched squealing or whining noise. This noise is often most noticeable when you start the engine or when you engage accessories like the air conditioner or power steering.

Rattling or Grinding Noise: A failing tensioner may also produce a rattling or grinding noise, especially at higher engine speeds or when the drive belt is under load.

Intermittent Noise: The noise produced by a failing belt tensioner can be intermittent, depending on factors like engine temperature and load.

Belt tensioner replacement

Replacing a belt tensioner is a relatively straightforward mechanical procedure, but it does require some mechanical knowledge and the right tools. Steps to follow when you are planning to replace your seal belt tensioner.

  1. Safety first: Ensure the engine is off, and the vehicle is secure. Disconnect the battery if necessary.
  2. Locate tensioner: Find the belt tensioner, usually a pulley on a bracket with a spring-loaded arm.
  3. Release belt tension: Use the right tool to rotate the tensioner arm, relieving tension on the drive belt.
  4. Remove belt: Carefully slide the belt off the pulleys. Note routing for reference.
  5. Remove old tensioner: Unbolt the old tensioner, keeping track of the hardware.
  6. Install new tensioner: Place the new tensioner in the same spot and secure it with bolts. Align it correctly.
  7. Reinstall belt: Put the belt back on the pulleys, ensuring proper alignment.
  8. Adjust tension: Use the tool to apply tension and follow the manufacturer's specs.
  9. Double-check: Confirm belt alignment and tension on all pulleys.
  10. Test: Start the engine, listen for issues, and check belt movement.
  11. Reconnect battery: If disconnected earlier, reconnect the vehicle's battery.
  12. Dispose of old parts: Properly dispose of the old tensioner and parts.

Related Blogs

Should You Replace the Tensioner When Replacing a Cracked Serpentine Belt?

Don't automatically replace the tensioner with a cracked serpentine belt. Check for weak spring force, misalignment, or noise. Replace both if the tensioner is worn; otherwise, swapping just the belt is often sufficient.

Aug 28, 2026