How do I replace the serpentine belt on a Infiniti Q45?

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 Infiniti Q45 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 Infiniti Q45?

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 Infiniti Q45?

Most Infiniti Q45 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.

⚙️Serpentine Belt

Infiniti Q45 Serpentine Belt

Find serpentine belt routing diagrams, part numbers, and replacement instructions for your Infiniti Q45. All years covered.

Quick Answer

The Infiniti Q45 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.

2001-2006

Belt 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

Shop on Amazon →Full Repair Guide →

1995-2000

Belt TypeMulti-rib serpentine (6PK or 7PK)

Belt Length85" - 100" (varies by engine and A/C option)

Tensioner TypeManual adjustment bolt or automatic

Replacement Interval60,000 - 100,000 miles

Notes

→Take a photo of the belt routing BEFORE removing the old belt
→Check if your model uses automatic or manual tensioner adjustment
→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

Shop on Amazon →Full Repair Guide →

1990-1994

Belt TypeMulti-rib serpentine (6PK or 7PK)

Belt Length85" - 100" (varies by engine and A/C option)

Tensioner TypeManual adjustment bolt or automatic

Replacement Interval60,000 - 100,000 miles

Notes

→Take a photo of the belt routing BEFORE removing the old belt
→Check if your model uses automatic or manual tensioner adjustment
→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

Shop on Amazon →Full Repair Guide →

Frequently Asked Questions

How do I replace the serpentine belt on a Infiniti Q45?: 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 Infiniti Q45 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 Infiniti Q45?: 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 Infiniti Q45?: Most Infiniti Q45 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.

Infiniti Q45 Repair Guides

→Infiniti Q45 Serpentine Belt Replacement →Infiniti Q45 Water Pump Replacement →Infiniti Q45 Alternator Replacement

Browse all Infiniti guides →Browse all Infiniti Q45 guides →

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