HomeBelts and Cooling > Accessory Drive Belt System ComponentsFour Seasons 45999 Accessory Drive Belt Idler Pulley
Part #: 45999

Four Seasons 45999 Accessory Drive Belt Idler Pulley

Pulley
⚙️ 26 vehicles fit this part
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OE Direct Replacement — Bolt-on fit, no modifications needed
📦Pulley
🚗Fitment: Ford, E-350 Super Duty, F-250 Super Duty, and F-350 Super Duty
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Reliable Accessory Drive Belt Idler Pulley for Ford Super Duty

The Four Seasons Pulley 45999 is a steel accessory drive belt idler pulley designed for Ford E-350 Super Duty, Excursion, F-250 Super Duty, and F-350 Super Duty models. Engineered to meet or exceed OEM specifications, this pulley ensures proper belt tension and smooth operation of your vehicle's accessory drive system.

  • Constructed from durable steel with a black finish for corrosion resistance
  • Compatible with flat back and serpentine belt types
  • Outside diameter of 3.5 inches (90 mm) and pulley width of 1.5 inches (38.1 mm)
  • Smooth groove design for optimal belt contact
  • Mounting hole diameter of 0.665 inches (17 mm), single mounting hole
  • Meets or exceeds OEM quality standards
  • Part number 45999 for precise fitment

Four Seasons Pulley Product Line Overview

The Four Seasons Pulley line focuses on accessory drive belt system components that provide reliable tension and idling functions. This product line emphasizes durability and exact fitment for specific vehicle applications, such as the Ford Super Duty series. The Pulley 45999 is part of this line, offering a steel construction and smooth surface designed to maintain proper belt alignment and tension under demanding conditions.

Detailed Product Description

This accessory drive belt idler pulley features a robust steel construction with a black finish to resist wear and corrosion. It has a smooth groove surface, suitable for flat back and serpentine belts, ensuring consistent belt tracking and tension. The pulley measures 3.5 inches in outside diameter and 1.5 inches in width, with a mounting hole diameter of 0.665 inches, designed for a secure fit on Ford E-350 Super Duty, Excursion, F-250 Super Duty, and F-350 Super Duty models. The Four Seasons 45999 pulley meets or exceeds OEM standards, providing a reliable replacement part for maintaining your vehicle's accessory drive system.

Common Applications and Issues Addressed

  • Restores proper belt tension and alignment in accessory drive systems
  • Eliminates belt slippage and noise caused by worn or damaged pulleys
  • Prevents premature belt wear and potential accessory component failure
  • Replaces faulty or seized idler pulleys in Ford Super Duty vehicles
  • Supports smooth operation of alternator, power steering, and air conditioning belts

Installation Notes and Tips

  • Verify compatibility with your specific Ford model and engine configuration before installation
  • Mounting hardware is not included; reuse existing hardware or source appropriate fasteners
  • Inspect belt condition and replace if necessary during pulley installation
  • Ensure proper torque specifications are followed to avoid pulley misalignment
  • Check belt routing and tension after installation for optimal performance

Quality Assurance and Warranty

The Four Seasons Pulley 45999 is manufactured to meet or exceed OEM quality standards, ensuring durability and reliable performance. While mounting hardware is not included, the pulley is engineered for a precise fit on compatible Ford Super Duty models. Please consult product documentation or manufacturer resources for warranty details.

BrandFour Seasons
Part Number45999
PositionPulley
Belt TypeFlat Back / Serpentine
Belt Width IN1.500
Belt Width MM38.0
Bore Dia. IN.67
ColorBlack
DescriptionIdler / Tensioner Pulley
Groove QuantitySmooth
I.D. MM17
Inside Diameter0.671875
MaterialSteel
Meets / Exceeds OEM?Yes
Mount Hole A Dia. MM17.000
Mount Hole Qty1
Mounting Hardware?Not Included
Mounting Hole Diameter0.665
Mounting Hole Quantity0.665
O.D. MM90.0
Outside Diameter3.500
Pulley TypeIdler Pulley
Pulley Width IN1.50
Pulley Width MM38.1
StyleIdler / Tensioner Pulley
TypePulley
Width38.1

This part fits 26 vehicles. Search below:

YearMakeModelLitersCylindersPositionNotes
2010FordE-350 Super Duty6.0LV8N/Aw/ Dual Alternator; Pulley
2010FordF-250 Super Duty6.4LV8N/Aw/ Dual Alternator; Pulley
2010FordF-350 Super Duty6.4LV8N/Aw/ Dual Alternator; Pulley
2009FordE-350 Super Duty6.0LV8N/Aw/ Dual Alternator; Pulley
2009FordF-250 Super Duty6.4LV8N/Aw/ Dual Alternator; Pulley
2009FordF-350 Super Duty6.4LV8N/Aw/ Dual Alternator; Pulley
2008FordE-350 Super Duty6.0LV8N/Aw/ Dual Alternator; Pulley
2008FordF-250 Super Duty6.4LV8N/Aw/ Dual Alternator; Pulley
2008FordF-350 Super Duty6.4LV8N/Aw/ Dual Alternator; Pulley
2007FordE-350 Super Duty6.0LV8N/Aw/ Dual Alternator; Pulley
2007FordF-250 Super Duty6.0LV8N/Aw/ Dual Alternator; Pulley
2007FordF-350 Super Duty6.0LV8N/ASmooth Pulley; Pulley
2006FordE-350 Super Duty6.0LV8N/Aw/ Dual Alternator; Pulley
2006FordF-250 Super Duty6.0LV8N/Aw/ Dual Alternator; Pulley
2006FordF-350 Super Duty6.0LV8N/ASmooth Pulley; Pulley
2005FordE-350 Super Duty6.0LV8N/Aw/ Dual Alternator; Pulley
2005FordExcursion6.0LV8N/ASmooth Pulley; Pulley
2005FordF-250 Super Duty6.0LV8N/Aw/ Dual Alternator; Pulley
2005FordF-350 Super Duty6.0LV8N/ASmooth Pulley; Pulley
2004FordE-350 Super Duty6.0LV8N/Aw/ Dual Alternator; Pulley
2004FordExcursion6.0LV8N/ASmooth Pulley; Pulley
2004FordF-250 Super Duty6.0LV8N/Aw/ Dual Alternator; Pulley
2004FordF-350 Super Duty6.0LV8N/Aw/ Dual Alternator; Pulley
2003FordExcursion6.0LV8N/ASmooth Pulley; Pulley
2003FordF-250 Super Duty6.0LV8N/ASmooth Pulley; Pulley
2003FordF-350 Super Duty6.0LV8N/ASmooth Pulley; Pulley

* Always verify fitment with your vehicle's VIN if unsure. Submodel & trim restrictions may apply.

This part directly replaces or is cross-referenced with the following part numbers:

3635439051390523C2E19A216AA3C2E19A216BA3C2Z8678AA3C3E19A216BB41965845999599983524589157A5625YS292YS313YS336

Cross-reference numbers are provided for identification purposes only. Always confirm fitment before ordering.