Dayco 5120903 | Serpentine Belt

Part Number
Serpentine Belt

Fits: 03-04 International 9200i SBA, 04-07 Mack CL, 04-07 Peterbilt 378, 04-07 Peterbilt 379, 04 Peterbilt 387, 06 Country Coach Motorhome Affinity, 08 Country Coach Motorhome Affinity

Special Price $49.61 Regular Price $58.36
In stock
Free Shipping
Estimated Ship Date: 1 Business Day or Less
The Dayco® Poly Rib® Belt is designed for power transmission on heavy duty multiple-accessory drives. This Poly Rib belt is the latest version of the revolutionary multi-ribbed belt first developed by Dayco® for the 1979 Ford® Mustang®. The Dayco® Poly Rib® Belt is manufactured from an extreme temperature EPDM rubber and features a construction that uses a highly fiber loaded compound to maximize belt life and load carrying requirements while minimizing pulley misalignment noise. This belt offers excellent resistance to high under hood temperatures and ozone contamination. In addition, specially formulated treated cord insures length and tension stability on heavy duty diesel engine drives for the life of the belt. The Dayco® Poly Rib® Belt meets or exceeds SAE J1459 and SAE J2432 specifications.

BRAND: Dayco




Cross SectionK-Section
Effective Length90.25
Effective Length2292.35
MaterialEPDM, Aramid Reinforced
Maximum Operating Temperature100
Maximum Operating Temperature212
Minimum Operating Temperature-45
Minimum Operating Temperature-42.7
Outside Circumference90.88
Outside Circumference2308.36
Rib DepthStandard
Rib ProfileStraight Rib
StandardsSAE J1459, SAE J2432
Top Width1.66



  • Navistar: 3565410-C1
  • Gates: K120903
  • NAPA: 25-120901
  • Oshkosh: 3823402
  • CARQUEST: 5120903HD
  • Navistar: 3829896C1
  • CARQUEST: K120901HD
  • Goodyear: 4120902
  • ACDelco: 12K903
  • Goodyear: 4120904
  • CARQUEST: K120901
  • Gates: K120903HD
  • Dynacraft: D84-1000-3122295
  • Dynacraft: D84-1000-1122295
  • Cummins: 3103836
  • Dynacraft: D1108-4216
  • NAPA: 25-120901HD
  • Dynacraft: D84-1000-6122295
  • ACDelco: 12K901
  • Cummins: 3682285
  • CARQUEST: K120903
  • Gates: K120901
  • Cummins: 3100189
  • NAPA: 25-120903
  • Gates: K120901HD
  • Cummins: 3682893
  • Dynacraft: D1108-5231


  • 2003-2004 International 9200i SBA - Position: Fan, Alternator and Water Pump
  • 2004-2007 Peterbilt 378 - Position: Fan and Alternator
  • 2004-2004 Peterbilt 387 - Position: Fan and Alternator
  • 2004-2007 Peterbilt 379 - Position: Fan and Alternator
  • 2004-2007 Mack CL - Position: Fan and Alternator
Customer Questions
Can a serpentine belt cause smoke?
Yes, a serpentine belt can cause smoke. A serpentine belt is an essential component of a vehicle's engine system. It drives various accessories such as the alternator, power steering pump, water pump, and air conditioning compressor. If the serpentine belt becomes worn, damaged, or misaligned, it can cause friction and generate smoke.
Why is my serpentine belt squealing?
The serpentine belt can squeal due to various reasons, including tension issues, worn-out belt, or a problem with the belt's pulleys.
Is my serpentine belt too tight?
If your serpentine belt is causing issues like excessive noise or accelerated wear on the pulleys, it may indicate that the belt is too tight.
Why did my serpentine belt come off?
Serpentine belts can come off due to factors such as belt wear, improper tension, misaligned pulleys, or a faulty tensioner.
Please, mind that only logged in users can submit questions

Compatible Vehicles


You may also be interested in

Copyright © 2013-present PartsHawk, LLC. All rights reserved.