⚙️Serpentine Belt
Buick LaCrosse Serpentine Belt
Find serpentine belt routing diagrams, part numbers, and replacement instructions for your Buick LaCrosse. All years covered.
Quick Answer
The Buick LaCrosse serpentine belt routes around the alternator, power steering pump, A/C compressor, and water pump. Belt length and routing vary by engine — see diagrams below.
2014-2019
2014-2019Belt TypeMulti-rib serpentine (6PK or 7PK)
Belt Length85" - 100" (varies by engine and A/C option)
Tensioner TypeAutomatic spring-loaded tensioner
Replacement Interval60,000 - 100,000 miles
Notes
- →Take a photo of the belt routing BEFORE removing the old belt
- →Use a 1/2" breaker bar or 15mm socket to release the automatic tensioner
- →Inspect the tensioner pulley and idler pulleys for bearing noise while the belt is off
- →A new belt may squeal briefly at startup — this usually stops within a few minutes
2008-2013
2008-2013Belt TypeMulti-rib serpentine (6PK or 7PK)
Belt Length85" - 100" (varies by engine and A/C option)
Tensioner TypeAutomatic spring-loaded tensioner
Replacement Interval60,000 - 100,000 miles
Notes
- →Take a photo of the belt routing BEFORE removing the old belt
- →Use a 1/2" breaker bar or 15mm socket to release the automatic tensioner
- →Inspect the tensioner pulley and idler pulleys for bearing noise while the belt is off
- →A new belt may squeal briefly at startup — this usually stops within a few minutes
2005-2007
2005-2007Belt TypeMulti-rib serpentine (6PK or 7PK)
Belt Length85" - 100" (varies by engine and A/C option)
Tensioner TypeAutomatic spring-loaded tensioner
Replacement Interval60,000 - 100,000 miles
Notes
- →Take a photo of the belt routing BEFORE removing the old belt
- →Use a 1/2" breaker bar or 15mm socket to release the automatic tensioner
- →Inspect the tensioner pulley and idler pulleys for bearing noise while the belt is off
- →A new belt may squeal briefly at startup — this usually stops within a few minutes
Frequently Asked Questions
- How do I replace the serpentine belt on a Buick LaCrosse?
- Release tension on the automatic tensioner with a breaker bar, slide the old belt off, route the new belt per the diagram (usually on a sticker under the hood), and release the tensioner onto the new belt. The job takes 15-30 minutes.
- How do I know if my Buick LaCrosse serpentine belt needs replacing?
- Signs include squealing at startup, visible cracks or fraying on the belt, loss of power steering or A/C, and the battery light coming on. Most belts should be replaced every 60,000-100,000 miles.
- What happens if the serpentine belt breaks on my Buick LaCrosse?
- If the serpentine belt breaks, you lose power steering, alternator charging, A/C, and (on some engines) the water pump. Pull over immediately — driving without the water pump will cause overheating and engine damage.
- Where is the belt routing diagram on a Buick LaCrosse?
- Most Buick LaCrosse models have a belt routing diagram on a sticker under the hood, near the radiator support or on the inner fender. If it's missing, check the service manual or see the diagrams below.