Dayco 5120985 Serpentine Belt - Fan or Fan and Air Conditioning
Dayco 5120985 Serpentine Belt Overview
The Dayco 5120985 serpentine belt is a K-section accessory drive belt built for long service in demanding engine bays. It uses EPDM rubber with aramid reinforcement to help maintain tension stability and resist wear across a wide temperature range.
Compatible With heavy-duty truck and diesel applications that use a 12-rib, K-section belt profile, including Freightliner, Cummins, and Navistar platforms. The Dayco 5120985 is also cross-referenced to common OE-style replacement numbers for the same application.
Key Features
- EPDM construction with aramid reinforcement for durability
- 12-rib, straight-rib design for accessory drive engagement
- K-section profile with a 1.66 in top width
- Effective length: 98.50 in (2501.90 mm)
- Outside circumference: 99.16 in (2518.67 mm)
- Black belt finish
- Operating temperature range: -45°F to 212°F
- Built to SAE J1459 and SAE J2432 standards
Detailed Description
Dayco 5120985 is a serpentine belt for accessory drive systems that require a 12-rib K-section belt with a 98.50-inch effective length. The EPDM compound is paired with aramid reinforcement to support consistent belt performance under heat, cold, and continuous engine loading. This makes it a practical choice for diesel and commercial-duty service where belt stability matters.
For buyers searching for a Dayco 5120985 serpentine belt, this part cross-references Gates K120985HD and ACDelco K120985HD for the same application. It is a direct-fit style replacement for select Freightliner, Cummins, and Navistar equipment that uses this belt specification.
What It Helps Address
- Squealing or slipping accessory drive belts
- Cracking, glazing, or rib wear on the existing belt
- Loss of belt tension from age and heat cycling
- Accessory drive noise from an aging serpentine belt
- Service replacement for a worn 12-rib diesel belt
Installation Notes and Tips
Verify the belt length, rib count, and K-section profile against the original belt before installation. Inspect pulleys, tensioners, and idlers for wear or misalignment, since those conditions can shorten belt life. Confirm routing against the vehicle’s belt diagram during service.
Fits 2006-2011 Freightliner, model-specific applications using this belt specification. Fits 2006-2011 Cummins, model-specific applications using this belt specification. Fits 2006-2011 Navistar, model-specific applications using this belt specification.
Quality Assurance
Dayco manufactures this belt to SAE J1459 and SAE J2432 standards, with EPDM and aramid reinforcement selected for durability in accessory drive service. The part number 5120985 is listed with OE-style interchange references for application matching.
Original: $83.10
-65%$83.10
$29.08Dayco 5120985 Serpentine Belt - Fan or Fan and Air Conditioning
Dayco 5120985 Serpentine Belt Overview
The Dayco 5120985 serpentine belt is a K-section accessory drive belt built for long service in demanding engine bays. It uses EPDM rubber with aramid reinforcement to help maintain tension stability and resist wear across a wide temperature range.
Compatible With heavy-duty truck and diesel applications that use a 12-rib, K-section belt profile, including Freightliner, Cummins, and Navistar platforms. The Dayco 5120985 is also cross-referenced to common OE-style replacement numbers for the same application.
Key Features
- EPDM construction with aramid reinforcement for durability
- 12-rib, straight-rib design for accessory drive engagement
- K-section profile with a 1.66 in top width
- Effective length: 98.50 in (2501.90 mm)
- Outside circumference: 99.16 in (2518.67 mm)
- Black belt finish
- Operating temperature range: -45°F to 212°F
- Built to SAE J1459 and SAE J2432 standards
Detailed Description
Dayco 5120985 is a serpentine belt for accessory drive systems that require a 12-rib K-section belt with a 98.50-inch effective length. The EPDM compound is paired with aramid reinforcement to support consistent belt performance under heat, cold, and continuous engine loading. This makes it a practical choice for diesel and commercial-duty service where belt stability matters.
For buyers searching for a Dayco 5120985 serpentine belt, this part cross-references Gates K120985HD and ACDelco K120985HD for the same application. It is a direct-fit style replacement for select Freightliner, Cummins, and Navistar equipment that uses this belt specification.
What It Helps Address
- Squealing or slipping accessory drive belts
- Cracking, glazing, or rib wear on the existing belt
- Loss of belt tension from age and heat cycling
- Accessory drive noise from an aging serpentine belt
- Service replacement for a worn 12-rib diesel belt
Installation Notes and Tips
Verify the belt length, rib count, and K-section profile against the original belt before installation. Inspect pulleys, tensioners, and idlers for wear or misalignment, since those conditions can shorten belt life. Confirm routing against the vehicle’s belt diagram during service.
Fits 2006-2011 Freightliner, model-specific applications using this belt specification. Fits 2006-2011 Cummins, model-specific applications using this belt specification. Fits 2006-2011 Navistar, model-specific applications using this belt specification.
Quality Assurance
Dayco manufactures this belt to SAE J1459 and SAE J2432 standards, with EPDM and aramid reinforcement selected for durability in accessory drive service. The part number 5120985 is listed with OE-style interchange references for application matching.
Product Information
Product Information
Shipping & Returns
Shipping & Returns
Description
Dayco 5120985 Serpentine Belt Overview
The Dayco 5120985 serpentine belt is a K-section accessory drive belt built for long service in demanding engine bays. It uses EPDM rubber with aramid reinforcement to help maintain tension stability and resist wear across a wide temperature range.
Compatible With heavy-duty truck and diesel applications that use a 12-rib, K-section belt profile, including Freightliner, Cummins, and Navistar platforms. The Dayco 5120985 is also cross-referenced to common OE-style replacement numbers for the same application.
Key Features
- EPDM construction with aramid reinforcement for durability
- 12-rib, straight-rib design for accessory drive engagement
- K-section profile with a 1.66 in top width
- Effective length: 98.50 in (2501.90 mm)
- Outside circumference: 99.16 in (2518.67 mm)
- Black belt finish
- Operating temperature range: -45°F to 212°F
- Built to SAE J1459 and SAE J2432 standards
Detailed Description
Dayco 5120985 is a serpentine belt for accessory drive systems that require a 12-rib K-section belt with a 98.50-inch effective length. The EPDM compound is paired with aramid reinforcement to support consistent belt performance under heat, cold, and continuous engine loading. This makes it a practical choice for diesel and commercial-duty service where belt stability matters.
For buyers searching for a Dayco 5120985 serpentine belt, this part cross-references Gates K120985HD and ACDelco K120985HD for the same application. It is a direct-fit style replacement for select Freightliner, Cummins, and Navistar equipment that uses this belt specification.
What It Helps Address
- Squealing or slipping accessory drive belts
- Cracking, glazing, or rib wear on the existing belt
- Loss of belt tension from age and heat cycling
- Accessory drive noise from an aging serpentine belt
- Service replacement for a worn 12-rib diesel belt
Installation Notes and Tips
Verify the belt length, rib count, and K-section profile against the original belt before installation. Inspect pulleys, tensioners, and idlers for wear or misalignment, since those conditions can shorten belt life. Confirm routing against the vehicle’s belt diagram during service.
Fits 2006-2011 Freightliner, model-specific applications using this belt specification. Fits 2006-2011 Cummins, model-specific applications using this belt specification. Fits 2006-2011 Navistar, model-specific applications using this belt specification.
Quality Assurance
Dayco manufactures this belt to SAE J1459 and SAE J2432 standards, with EPDM and aramid reinforcement selected for durability in accessory drive service. The part number 5120985 is listed with OE-style interchange references for application matching.
