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Four Seasons 45999 Accessory Drive Belt Idler Pulley
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.
| Brand | Four Seasons |
| Part Number | 45999 |
| Position | Pulley |
| Belt Type | Flat Back / Serpentine |
| Belt Width IN | 1.500 |
| Belt Width MM | 38.0 |
| Bore Dia. IN | .67 |
| Color | Black |
| Description | Idler / Tensioner Pulley |
| Groove Quantity | Smooth |
| I.D. MM | 17 |
| Inside Diameter | 0.671875 |
| Material | Steel |
| Meets / Exceeds OEM? | Yes |
| Mount Hole A Dia. MM | 17.000 |
| Mount Hole Qty | 1 |
| Mounting Hardware? | Not Included |
| Mounting Hole Diameter | 0.665 |
| Mounting Hole Quantity | 0.665 |
| O.D. MM | 90.0 |
| Outside Diameter | 3.500 |
| Pulley Type | Idler Pulley |
| Pulley Width IN | 1.50 |
| Pulley Width MM | 38.1 |
| Style | Idler / Tensioner Pulley |
| Type | Pulley |
| Width | 38.1 |
This part fits 26 vehicles. Search below:
| Year | Make | Model | Liters | Cylinders | Position | Notes |
|---|---|---|---|---|---|---|
| 2010 | Ford | E-350 Super Duty | 6.0L | V8 | N/A | w/ Dual Alternator; Pulley |
| 2010 | Ford | F-250 Super Duty | 6.4L | V8 | N/A | w/ Dual Alternator; Pulley |
| 2010 | Ford | F-350 Super Duty | 6.4L | V8 | N/A | w/ Dual Alternator; Pulley |
| 2009 | Ford | E-350 Super Duty | 6.0L | V8 | N/A | w/ Dual Alternator; Pulley |
| 2009 | Ford | F-250 Super Duty | 6.4L | V8 | N/A | w/ Dual Alternator; Pulley |
| 2009 | Ford | F-350 Super Duty | 6.4L | V8 | N/A | w/ Dual Alternator; Pulley |
| 2008 | Ford | E-350 Super Duty | 6.0L | V8 | N/A | w/ Dual Alternator; Pulley |
| 2008 | Ford | F-250 Super Duty | 6.4L | V8 | N/A | w/ Dual Alternator; Pulley |
| 2008 | Ford | F-350 Super Duty | 6.4L | V8 | N/A | w/ Dual Alternator; Pulley |
| 2007 | Ford | E-350 Super Duty | 6.0L | V8 | N/A | w/ Dual Alternator; Pulley |
| 2007 | Ford | F-250 Super Duty | 6.0L | V8 | N/A | w/ Dual Alternator; Pulley |
| 2007 | Ford | F-350 Super Duty | 6.0L | V8 | N/A | Smooth Pulley; Pulley |
| 2006 | Ford | E-350 Super Duty | 6.0L | V8 | N/A | w/ Dual Alternator; Pulley |
| 2006 | Ford | F-250 Super Duty | 6.0L | V8 | N/A | w/ Dual Alternator; Pulley |
| 2006 | Ford | F-350 Super Duty | 6.0L | V8 | N/A | Smooth Pulley; Pulley |
| 2005 | Ford | E-350 Super Duty | 6.0L | V8 | N/A | w/ Dual Alternator; Pulley |
| 2005 | Ford | Excursion | 6.0L | V8 | N/A | Smooth Pulley; Pulley |
| 2005 | Ford | F-250 Super Duty | 6.0L | V8 | N/A | w/ Dual Alternator; Pulley |
| 2005 | Ford | F-350 Super Duty | 6.0L | V8 | N/A | Smooth Pulley; Pulley |
| 2004 | Ford | E-350 Super Duty | 6.0L | V8 | N/A | w/ Dual Alternator; Pulley |
| 2004 | Ford | Excursion | 6.0L | V8 | N/A | Smooth Pulley; Pulley |
| 2004 | Ford | F-250 Super Duty | 6.0L | V8 | N/A | w/ Dual Alternator; Pulley |
| 2004 | Ford | F-350 Super Duty | 6.0L | V8 | N/A | w/ Dual Alternator; Pulley |
| 2003 | Ford | Excursion | 6.0L | V8 | N/A | Smooth Pulley; Pulley |
| 2003 | Ford | F-250 Super Duty | 6.0L | V8 | N/A | Smooth Pulley; Pulley |
| 2003 | Ford | F-350 Super Duty | 6.0L | V8 | N/A | Smooth 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:
Cross-reference numbers are provided for identification purposes only. Always confirm fitment before ordering.