Western Star 4900EX Idler Pulleys

Your Western Star 4900EX will be happy to know that the search for the right Idler Pulleys you’ve been looking for is over! Advance Auto Parts has 14 different Idler Pulleys for your vehicle, ready for shipping or in-store pick up. The best part is, our Western Star 4900EX Idler Pulleys start from as little as $25.99.

When it comes to your Western Star 4900EX, you want parts and products from only trusted brands. Here at Advance Auto Parts, we work with only top reliable Idler Pulleys brands so you can shop with complete confidence. Some of our top Idler Pulleys brands are Dayco and Litens. We’re sure you will get the right product to keep that 4900EX running for a long time.

We even have reviews of our OEM and aftermarket Idler Pulleys products to help you buy with confidence. Hear from other customers via the 79 reviews on parts for your Western Star 4900EX.

Shop online, find the best price on the right product, and have it shipped right to your door. If you prefer to shop in person for the right Idler Pulleys for your 4900EX, visit one of our local Advance Auto Parts locations and you’ll be back on the road in no time!

Compare 23 Western Star Idler Pulleys

Dayco – Serpentine Idler/Tensioner Pulley; Direct Fit, 76 mm Diameter, 37 mm Smooth (Part No.89016)

Serpentine Idler/Tensioner Pulley; Direct Fit, 76 mm Diameter, 37 mm Smooth

from

$25.99
Dayco idler/tensioner pulleys are built with smoother surfaces and tighter dimensional tolerances, which translates to less vibration and longer belt life. In addition to stamped, forged steel and powdered metal pulleys, Dayco also designs ultra-strong pl

Product Features:
  • Designed for the majority of automotive vehicle applications on the road today
  • High-quality materials help resist wear and improve belt life
  • Features premium lubricated bearings to extend service life
  • Meets or exceeds OE quality
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Dayco – Serpentine Assy. Idler/Tensioner Pulley; Steel, 77mm Dia., 30mm Width, 6 Grooves (Part No.89171)

Serpentine Assy. Idler/Tensioner Pulley; Steel, 77mm Dia., 30mm Width, 6 Grooves

from

$56.99
Dayco idler/tensioner pulleys are built with smoother surfaces and tighter dimensional tolerances, which translates to less vibration and longer belt life. In addition to stamped, forged steel and powdered metal pulleys, Dayco also designs ultra-strong plastic pulleys with specially formulated glass-filled polymers that resist wear & tear. Premium lubricated ball bearings and double high temperature seals ensure peak bearing performance, the most critical element of a pulley’s service life.

Product Features:
  • Designed for the majority of automotive vehicle applications on the road today.
  • High-quality materials help resist wear and improve belt life
  • Features premium lubricated bearings to extend service life
  • Meets or exceeds OE quality
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Litens – O.E Quality Idler/Tensioner Pulley: Direct Fit, Steel, 78 mm Diameter (Part No.900466A)

O.E Quality Idler/Tensioner Pulley: Direct Fit, Steel, 78 mm Diameter

from

$62.99
This pulley is supplied by Litens Automotive – inventor of the first automatic belt tensioner in 1979 and today the world’s largest supplier of Original Equipment (O.E.) belt tensioning and routing products. This pulley is produced for serpentine belt routing applications and as the pulley component on automatic tensioner applications. This pulley conforms to original equipment material, tolerances, and specifications. The part meets all performance and durability requirements. Fits Heavy Duty truck applications including the Mack LE Series. Litens is the world’s largest supplier of original equipment (O.E.) power transmission products. At Litens, we design systems that are more efficient, resulting in tangible fuel economy/emissions benefits. Litens holds over 2000 patents and continues to respond to the ever-changing automotive industry by investing heavily in new technology, facilities, and people. 90% of our line is made of products coming from the OE manufacturer, which makes the Litens Tensioning Products portfolio the purest OE tensioning line in the North American aftermarket._

Product Features:
  • Manufactured by one of the world’s largest Original Equipment suppliers of accessory drive tensioners and pulleys
  • Heavy Duty Steel Pulley
  • Precision steel stamping with close tolerance ball bearing pocket.
  • Electro-deposited coating (e-coat) for superior corrosion resistance.
  • Running surface designed and engineered for proper belt tracking.
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Dayco No Slack Gold Label – Serpentine Idler/Tensioner Pulley; Steel, 86.5mm Dia., 39.4mm Width, Smooth (Part No.89106)

Serpentine Idler/Tensioner Pulley; Steel, 86.5mm Dia., 39.4mm Width, Smooth

from

$57.99
Designed to replace idler and tensioner pulleys for serpentine drives in heavy-duty diesel engine applications, Dayco HD idler/tensioner pulleys are machined from high-strength steel or powdered metal material to provide excellent wear resistance under ha

Product Features:
  • Engineered for the demanding drive systems of today’s class 4-8 heavy-duty commercial trucks
  • Premium OE technology to ensure peak performance under extreme conditions
  • Utilizes 3D dimensional computer aided design (CAD) and finite element analysis (FEA) for optimal design and maximum structural integrity
  • Meets or exceeds OE quality
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Dayco No Slack Gold Label – Serpentine Idler/Tensioner Pulley; Steel, 74mm Dia., 38.3mm Width, Smooth (Part No.89111)

Serpentine Idler/Tensioner Pulley; Steel, 74mm Dia., 38.3mm Width, Smooth

from

$86.99
Designed to replace idler and tensioner pulleys for serpentine drives in heavy-duty diesel engine applications, Dayco HD idler/tensioner pulleys are machined from high-strength steel or powdered metal material to provide excellent wear resistance under ha

Product Features:
  • Engineered for the demanding drive systems of today’s class 4-8 heavy-duty commercial trucks
  • Premium OE technology to ensure peak performance under extreme conditions
  • Utilizes 3D dimensional computer aided design (CAD) and finite element analysis (FEA) for optimal design and maximum structural integrity
  • Meets or exceeds OE quality
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Gates – DRIVEALIGN PULLEY (Part No.36096)

DRIVEALIGN PULLEY

from

$95.99
DRIVEALIGN PULLEY

Gates – DriveAlign½ Belt Drive Idler/Tensioner Pulley (Part No.36227)

DriveAlign½ Belt Drive Idler/Tensioner Pulley

from

$44.99
Product Features:
  • Steel and thermoplastic construction designed to tight manufacturing tolerances for high durability and quality performance
  • Built to last with a superior resistance to dirt, salt, chemicals and other under-hood contaminants
  • OE-quality fit for virtually every domestic or import vehicle on the road today
  • Bearings meet or exceed OE standards with application-specific speed and load requirements, to withstand high under hood temperatures
  • Premium bearings eliminate bearing noise
  • Mounting hardware included for some popular applications
  • Reliable operation under severe conditions
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Dayco No Slack Gold Label – Serpentine Idler/Tensioner Pulley; Steel, 74mm Dia., 46.27mm Width, Smooth (Part No.89102)

Serpentine Idler/Tensioner Pulley; Steel, 74mm Dia., 46.27mm Width, Smooth

from

$54.99
Designed to replace idler and tensioner pulleys for serpentine drives in heavy-duty diesel engine applications, Dayco HD idler/tensioner pulleys are machined from high-strength steel or powdered metal material to provide excellent wear resistance under ha

Product Features:
  • Engineered for the demanding drive systems of today’s class 4-8 heavy-duty commercial trucks
  • Premium OE technology to ensure peak performance under extreme conditions
  • Utilizes 3D dimensional computer aided design (CAD) and finite element analysis (FEA) for optimal design and maximum structural integrity
  • Meets or exceeds OE quality
See More

Gates – DriveAlign½ Belt Drive Idler/Tensioner Pulley (Part No.36302)

DriveAlign½ Belt Drive Idler/Tensioner Pulley

from

$228.99
Product Features:
  • Steel and thermoplastic construction designed to tight manufacturing tolerances for high durability and quality performance
  • Built to last with a superior resistance to dirt, salt, chemicals and other under-hood contaminants
  • OE-quality fit for virtually every domestic or import vehicle on the road today
  • Bearings meet or exceed OE standards with application-specific speed and load requirements, to withstand high under hood temperatures
  • Premium bearings eliminate bearing noise
  • Mounting hardware included for some popular applications
  • Reliable operation under severe conditions
See More

Litens – O.E Quality Idler/Tensioner Pulley: Direct Fit, Steel, 75 mm Diameter (Part No.900614A)

O.E Quality Idler/Tensioner Pulley: Direct Fit, Steel, 75 mm Diameter

from

$171.99
This pulley is manufactured by one of the largest original equipment pulley suppliers to ensure proper fit and performance. This pulley is produced for 2006-2010 Freightliner Classic, Bus Class M2, Cascadia, Century Class, Columbia / Sterling A-Line, L-Line with 4000 Diesel It’s a serpentine belt routing application and conforms to original equipment material, tolerances, and specifications. This replacement part is made to the O.E. specified design and meets all performance and durability requirements. Heavy Duty Steel Pulley with close tolerance ball bearing pocket and Electro-deposited coating for superior corrosion resistance. This pulley comes with a dust shield, installation bolt and retainer. Litens is the world’s largest supplier of original equipment (O.E.) power transmission products. At Litens, we design systems that are more efficient, resulting in tangible fuel economy/emissions benefits. Litens holds over 2000 patents and continues to respond to the ever-changing automotive industry by investing heavily in new technology, facilities, and people. 90% of our line is made of products coming from the OE manufacturer, which makes the Litens Tensioning Products portfolio the purest OE tensioning line in the North American aftermarket.
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Gates – DriveAlign½ Belt Drive Idler/Tensioner Pulley (Part No.36226)

DriveAlign½ Belt Drive Idler/Tensioner Pulley

from

$170.99
Product Features:
  • Steel and thermoplastic construction designed to tight manufacturing tolerances for high durability and quality performance
  • Built to last with a superior resistance to dirt, salt, chemicals and other under-hood contaminants
  • OE-quality fit for virtually every domestic or import vehicle on the road today
  • Bearings meet or exceed OE standards with application-specific speed and load requirements, to withstand high under hood temperatures
  • Premium bearings eliminate bearing noise
  • Mounting hardware included for some popular applications
  • Reliable operation under severe conditions
See More

Gates – DriveAlign½ Belt Drive Idler/Tensioner Pulley (Part No.36269)

DriveAlign½ Belt Drive Idler/Tensioner Pulley

from

$148.99
Product Features:
  • Steel and thermoplastic construction designed to tight manufacturing tolerances for high durability and quality performance
  • Built to last with a superior resistance to dirt, salt, chemicals and other under-hood contaminants
  • OE-quality fit for virtually every domestic or import vehicle on the road today
  • Bearings meet or exceed OE standards with application-specific speed and load requirements, to withstand high under hood temperatures
  • Premium bearings eliminate bearing noise
  • Mounting hardware included for some popular applications
  • Reliable operation under severe conditions
See More

Litens – O.E Quality Idler/Tensioner Pulley: Direct Fit, Steel, 86.5 mm Diameter (Part No.900379A)

O.E Quality Idler/Tensioner Pulley: Direct Fit, Steel, 86.5 mm Diameter

from

$136.99
This pulley is supplied by Litens Automotive – inventor of the first automatic belt tensioner in 1979 and today the world’s largest supplier of Original Equipment (O.E.) belt tensioning and routing products. This pulley is produced for serpentine belt routing applications and as the pulley component on automatic tensioner applications. This pulley conforms to original equipment material, tolerances, and specifications. The part meets all performance and durability requirements. Fits Heavy Duty truck applications including Freightliner Argosy and FLD. Comes complete with new bolt, washer, and spacer. Litens is the world’s largest supplier of original equipment (O.E.) power transmission products. At Litens, we design systems that are more efficient, resulting in tangible fuel economy/emissions benefits. Litens holds over 2000 patents and continues to respond to the ever-changing automotive industry by investing heavily in new technology, facilities, and people. 90% of our line is made of products coming from the OE manufacturer, which makes the Litens Tensioning Products portfolio the purest OE tensioning line in the North American aftermarket.
See More

Litens – O.E Quality Idler/Tensioner Pulley: Direct Fit, Steel, 74 mm Diameter (Part No.900454A)

O.E Quality Idler/Tensioner Pulley: Direct Fit, Steel, 74 mm Diameter

from

$109.99
This pulley is supplied by Litens Automotive – inventor of the first automatic belt tensioner in 1979 and today the world’s largest supplier of Original Equipment (O.E.) belt tensioning and routing products. This pulley is produced for serpentine belt routing applications and as the pulley component on automatic tensioner applications. This pulley conforms to original equipment material, tolerances, and specifications. The part meets all performance and durability requirements. Fits Heavy Duty truck applications including Freightliner Columbia. Comes complete with new bolt, washer/dust cover, and spacer. Litens is the world’s largest supplier of original equipment (O.E.) power transmission products. At Litens, we design systems that are more efficient, resulting in tangible fuel economy/emissions benefits. Litens holds over 2000 patents and continues to respond to the ever-changing automotive industry by investing heavily in new technology, facilities, and people. 90% of our line is made of products coming from the OE manufacturer, which makes the Litens Tensioning Products portfolio the purest OE tensioning line in the North American aftermarket._

Product Features:
  • Manufactured by the world’s largest Original Equipment supplier of accessory drive tensioners and pulleys
  • Heavy Duty Steel Pulley for Freightliner Trucks
  • Pre-assembled pulleys save installation time and ensure that all components are assembled to original specifications for both installation and performance
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Gates – DriveAlign½ Belt Drive Idler/Tensioner Pulley (Part No.36341)

DriveAlign½ Belt Drive Idler/Tensioner Pulley

from

$105.99
Product Features:
  • Steel and thermoplastic construction designed to tight manufacturing tolerances for high durability and quality performance
  • Built to last with a superior resistance to dirt, salt, chemicals and other under-hood contaminants
  • OE-quality fit for virtually every domestic or import vehicle on the road today
  • Bearings meet or exceed OE standards with application-specific speed and load requirements, to withstand high under hood temperatures
  • Premium bearings eliminate bearing noise
  • Mounting hardware included for some popular applications
  • Reliable operation under severe conditions
See More

Litens – O.E Quality Idler/Tensioner Pulley: Direct Fit, Steel, 74 mm Diameter (Part No.900566A)

O.E Quality Idler/Tensioner Pulley: Direct Fit, Steel, 74 mm Diameter

from

$90.99
This Litens pulley is manufactured by one of the largest original equipment pulley suppliers to ensure proper fit and performance. This pulley is produced for serpentine belt routing applications and is made of high strength steel for improved life and durability. This pulley conforms to original equipment material, tolerances, and specifications. This part fits Heavy Duty truck applications including 2000-2008 Kenworth with C13/C15. Comes pre-assembled with a new installation bolt and dust shield. Litens is the world’s largest supplier of original equipment (O.E.) power transmission products. At Litens, we design systems that are more efficient, resulting in tangible fuel economy/emissions benefits. Litens holds over 2000 patents and continues to respond to the ever-changing automotive industry by investing heavily in new technology, facilities, and people. 90% of our line is made of products coming from the OE manufacturer, which makes the Litens Tensioning Products portfolio the purest OE tensioning line in the North American aftermarket.
See More

Litens – O.E Quality Idler/Tensioner Pulley: Direct Fit, Steel, 74 mm Diameter (Part No.900301A)

O.E Quality Idler/Tensioner Pulley: Direct Fit, Steel, 74 mm Diameter

from

$77.99
This Litens pulley is manufactured by one of the largest original equipment pulley suppliers to ensure proper fit and performance. This pulley is produced for serpentine belt routing applications and conforms to original equipment material, tolerances, and specifications. This replacement part is made in Canada to the O.E. specified design and meets all performance and durability requirements. This Heavy duty Steel pulley is 74.1mm O.D. Applications include HD Truck and Bus applications Litens is the world’s largest supplier of original equipment (O.E.) power transmission products. At Litens, we design systems that are more efficient, resulting in tangible fuel economy/emissions benefits. Litens holds over 2000 patents and continues to respond to the ever-changing automotive industry by investing heavily in new technology, facilities, and people. 90% of our line is made of products coming from the OE manufacturer, which makes the Litens Tensioning Products portfolio the purest OE tensioning line in the North American aftermarket.
See More

Gates – DriveAlign½ Belt Drive Idler/Tensioner Pulley (Part No.36230)

DriveAlign½ Belt Drive Idler/Tensioner Pulley

from

$66.99
Product Features:
  • Steel and thermoplastic construction designed to tight manufacturing tolerances for high durability and quality performance
  • Built to last with a superior resistance to dirt, salt, chemicals and other under-hood contaminants
  • OE-quality fit for virtually every domestic or import vehicle on the road today
  • Bearings meet or exceed OE standards with application-specific speed and load requirements, to withstand high under hood temperatures
  • Premium bearings eliminate bearing noise
  • Mounting hardware included for some popular applications
  • Reliable operation under severe conditions
See More

Dayco No Slack Gold Label – Serpentine Idler/Tensioner Pulley; Steel, 74mm Dia., 42.6mm Width, Smooth (Part No.89109)

Serpentine Idler/Tensioner Pulley; Steel, 74mm Dia., 42.6mm Width, Smooth

from

$65.99
Designed to replace idler and tensioner pulleys for serpentine drives in heavy-duty diesel engine applications, Dayco HD idler/tensioner pulleys are machined from high-strength steel or powdered metal material to provide excellent wear resistance under ha

Product Features:
  • Engineered for the demanding drive systems of today’s class 4-8 heavy-duty commercial trucks
  • Premium OE technology to ensure peak performance under extreme conditions
  • Utilizes 3D dimensional computer aided design (CAD) and finite element analysis (FEA) for optimal design and maximum structural integrity
  • Meets or exceeds OE quality
See More

Litens – O.E Quality Idler/Tensioner Pulley: Direct Fit, Steel, 74 mm Diameter (Part No.900506A)

O.E Quality Idler/Tensioner Pulley: Direct Fit, Steel, 74 mm Diameter

from

$63.99
This pulley is supplied by Litens Automotive – inventor of the first automatic belt tensioner in 1979 and today the world’s largest supplier of Original Equipment (O.E.) belt tensioning and routing products. This pulley is produced for serpentine belt routing applications and as the pulley component on automatic tensioner applications. This pulley conforms to original equipment material, tolerances, and specifications. The part meets all performance and durability requirements. Fits Heavy Duty truck applications including Kenworth. Peterbilt, Freightliner, and Western Star. Comes pre-assembled with a new installation bolt and washer. Litens is the world’s largest supplier of original equipment (O.E.) power transmission products. At Litens, we design systems that are more efficient, resulting in tangible fuel economy/emissions benefits. Litens holds over 2000 patents and continues to respond to the ever-changing automotive industry by investing heavily in new technology, facilities, and people. 90% of our line is made of products coming from the OE manufacturer, which makes the Litens Tensioning Products portfolio the purest OE tensioning line in the North American aftermarket.
See More

Litens – O.E Quality Idler/Tensioner Pulley: Direct Fit, Steel, 75 mm Diameter (Part No.900276A)

O.E Quality Idler/Tensioner Pulley: Direct Fit, Steel, 75 mm Diameter

from

$60.99
This Litens pulley is manufactured by one of the largest original equipment pulley suppliers to ensure proper fit and performance. This pulley is produced for serpentine belt routing applications and conforms to original equipment material, tolerances, and specifications. This replacement part is made in Canada to the O.E. specified design and meets all performance and durability requirements. This Heavy duty Steel pulley is 74mm O.D. Applications include HD Truck and Bus applications Litens is the world’s largest supplier of original equipment (O.E.) power transmission products. At Litens, we design systems that are more efficient, resulting in tangible fuel economy/emissions benefits. Litens holds over 2000 patents and continues to respond to the ever-changing automotive industry by investing heavily in new technology, facilities, and people. 90% of our line is made of products coming from the OE manufacturer, which makes the Litens Tensioning Products portfolio the purest OE tensioning line in the North American aftermarket.
See More

Litens – O.E Quality Idler/Tensioner Pulley: Direct Fit, Steel, 70 mm Diameter (Part No.900657A)

O.E Quality Idler/Tensioner Pulley: Direct Fit, Steel, 70 mm Diameter

from

$56.99
This Litens Idler Pulley is manufactured by one of the world’s largest original equipment pulley suppliers to ensure proper fit and performance. The part is made using the O.E. specified design and meets all performance and durability requirements. Heavy duty steel construction for long life and trouble-free performance. Designed for HD truck applications. Litens is the world’s largest supplier of original equipment (O.E.) power transmission products. At Litens, we design systems that are more efficient, resulting in tangible fuel economy/emissions benefits. Litens holds over 2000 patents and continues to respond to the ever-changing automotive industry by investing heavily in new technology, facilities, and people. 90% of our line is made of products coming from the OE manufacturer, which makes the Litens Tensioning Products portfolio the purest OE tensioning line in the North American aftermarket._

Product Features:
  • Designed and engineered by the Original Equipment supplier of this application
  • Forged Heavy Duty Steel Pulley designed to displace bearing heat. Precision machined face for smooth running surface.
  • Lower Idler Pulley Position
  • Pulley Specs: 70mm (OD) x 10mm (ID -Inner Bore) x 18mm (ID – Inner Bore) x 34mm (Width).
  • Smooth/Backside – Steel Pulley.
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Litens – O.E Quality Idler/Tensioner Pulley: Direct Fit, Steel, 75 mm Diameter (Part No.900041A)

O.E Quality Idler/Tensioner Pulley: Direct Fit, Steel, 75 mm Diameter

from

$53.99
This pulley is supplied by Litens Automotive – inventor of the first automatic belt tensioner in 1979 and today the world’s largest supplier of Original Equipment (O.E.) belt tensioning and routing products. This pulley is produced for serpentine belt routing applications and as the pulley component on automatic tensioner applications. This pulley conforms to original equipment material, tolerances, and specifications. The part meets all performance and durability requirements. Fits Heavy Duty truck applications including Freightliner, Kenworth, Peterbilt, Sterling, and Western Star. Litens is the world’s largest supplier of original equipment (O.E.) power transmission products. At Litens, we design systems that are more efficient, resulting in tangible fuel economy/emissions benefits. Litens holds over 2000 patents and continues to respond to the ever-changing automotive industry by investing heavily in new technology, facilities, and people. 90% of our line is made of products coming from the OE manufacturer, which makes the Litens Tensioning Products portfolio the purest OE tensioning line in the North American aftermarket.
See More

FAQs for Western Star 4900EX Idler Pulleys

What are the most popular Idler Pulleys for the Western Star 4900EX?

With 3 brands you can trust, our most popular Idler Pulleys for the Western Star 4900EX are: