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Dayco HD Belt Tensioner - 74 mm Pulley x 38 mm Wide - Dayco 89458 DAY89458
Dayco HD Belt Tensioner - 74 mm Pulley x 38 mm Wide - Dayco 89458 DAY89458
Dayco

Dayco HD Belt Tensioner - 74 mm Pulley x 38 mm Wide - Dayco 89458 DAY89458

In stock
SKU: DAY89458
$168.66
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Fitment

Fits these trucks

Heavy-duty truck diesel enginesSerpentine belt drive - automatic tensioner positionConfirm against the Dayco application guide
Always confirm your year, make & model before ordering.
Part numbers

OEM & interchange numbers

1 cross-ref
Dayco 89458
Direct 1-to-1 replacement for every number above. Tap any number to copy.
Overview

Put the tension back in the serpentine drive with this Dayco Heavy-Duty Automatic Belt Tensioner distributed by FleetPro Parts & Tires. Dayco builds this one to OE grade, and its job is simple and unglamorous: hold steady, correct tension on the serpentine belt of a heavy-duty diesel engine, mile after mile, so the belt keeps its grip on everything it drives. Leave a tired tensioner on the engine and you start buying belts on a schedule instead of on a need. We stock these heavily right here in our Hanover Park, Illinois warehouse to ensure lightning-fast shipping for fleets, diesel repair shops, and owner-operators nationwide.

OE-Grade Tension Control: The Dayco HD Tensioner Advantage

Belt tension is not a set-and-forget number. It has to stay inside a narrow band while the engine swings from cold idle to full load, and it is a spring and a bearing that hold that band. This assembly runs a 74 mm pulley that is 38 mm wide, the contact face that carries the belt and does the actual work, and it arrives as a complete unit so the spring, the arm and the pulley are all new together. Fitting a fresh belt to a used tensioner is the most common way a good belt job goes wrong.

At FleetPro Parts & Tires, we would rather send you the part that carries the OE grade than the cheapest thing on the shelf that fits. This is a genuine Dayco unit, new, and backed by the 1-Year FleetPro Warranty. It is ordered and cross-referenced in the industry as 89458. Because this tensioner covers a range of heavy-duty truck engines, check the Dayco application guide against your engine before you order, and plan to replace the belt at the same time. A tensioner and a belt are a matched pair.

Vehicle Fitment & Compatibility

This OE-grade heavy-duty tensioner is intended for the following commercial applications:

  • Application: Heavy-duty truck diesel engines
  • Belt Type: Serpentine
  • Position: Automatic tensioner on the serpentine belt drive
  • Verification: Confirm against the Dayco application guide for your engine
  • Component Group: Engine Accessory Drive / Belts & Tensioners

Direct Replacement & Cross-Reference Numbers:

Order this Dayco heavy-duty tensioner by the following part numbers:

  • Dayco Interchange: 89458
  • FleetPro Part #: DAY89458

Technical Specifications

  • Component Type: Heavy-Duty Automatic Belt Tensioner
  • Pulley Diameter: 74 mm
  • Pulley Width: 38 mm
  • Belt Type: Serpentine
  • Grade: OE
  • Condition: New
  • Warranty: 1-Year FleetPro Warranty
  • Product Level: OEM
  • Brand: Dayco (Distributed by FleetPro Parts & Tires)
Key features
  • Genuine Dayco OE Grade: Dayco builds this tensioner to OE grade, so the assembly you bolt on carries the quality level the engine was designed around.
  • 74 mm Pulley, 38 mm Wide: The pulley diameter and the contact width that carries the belt are the two dimensions that have to match, and both are specified.
  • Complete Assembly: Spring, arm and pulley arrive together as one unit instead of a bearing kit that reuses the tired half of the pair.
  • Serpentine Belt Duty: Purpose-built to maintain serpentine belt tension on heavy-duty diesel engines.
  • Backed by FleetPro: New Dayco hardware covered by the 1-Year FleetPro Warranty.
Specifications
Component Type
Heavy-Duty Automatic Belt Tensioner
Pulley Diameter
74 mm
Pulley Width
38 mm
Belt Type
Serpentine
Grade
OE
Condition
New
Warranty
1-Year FleetPro Warranty
UPC
036687485519
Product Level
OEM
Questions
Will this fit my truck?
This part fits Heavy-duty truck diesel engines, Serpentine belt drive - automatic tensioner position, Confirm against the Dayco application guide. Always confirm your year, make and model before ordering.
What part numbers does it replace?
Yes. It is a direct replacement that interchanges with Dayco 89458.
How fast does it ship?
In-stock orders placed before 12 PM Central on business days ship the same day from our Hanover Park, IL warehouse, and typically arrive in 2 to 5 business days anywhere in the USA.
What's your return policy?
Unused items in original packaging can be returned within 30 days, backed by our 30-day money-back guarantee. If we ship the wrong part, we cover the return label and send the correct one.