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Dayco 5040685 Serpentine Belt - Main DriveOE Quality 60-Day Returns
Part #: 5040685

Dayco 5040685 Serpentine Belt - Main Drive

Main Drive
113 vehicles fit this part
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Fitment: Chevrolet and GMC, Astro, C1500, C2500, C3500, G10, G1500, G20, G2500, G30, G3500, K1500, K2500, K3500, and Safari
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Dayco 5040685 Serpentine Belt Overview

The Dayco 5040685 serpentine belt is a 4-rib accessory drive belt built for specific GM truck, van, and utility applications that use a main drive belt without power steering, air pump, or air conditioning. It uses EPDM rubber with aramid reinforcement for stable operation across a wide temperature range.

  • EPDM, aramid reinforced construction for durability
  • 4-rib K-section design with straight rib profile
  • Black belt with .54 in top width
  • Effective length: 68.50 in (1739.90 mm)
  • Outside circumference: 69.06 in (1754.13 mm)
  • Operating temperature range: -45°F to 212°F
  • Meets SAE J1459 and SAE J2432 standards

Fitment and Application Details

Compatible With 1987-1989 Chevrolet Astro, Main Drive; 1988-1989 Chevrolet C1500, Main Drive; 1988-1989 Chevrolet C2500, Main Drive; 1988-1989 Chevrolet C3500, Main Drive; 1987-1989 Chevrolet G10, Main Drive; 1987-1989 Chevrolet G20, Main Drive; 1987-1989 Chevrolet G30, Main Drive; 1988-1989 Chevrolet K1500, Main Drive; 1988-1989 Chevrolet K2500, Main Drive; 1988-1989 Chevrolet K3500, Main Drive; 1988-1989 GMC C1500, Main Drive; 1988-1989 GMC C2500, Main Drive; 1988-1989 GMC C3500, Main Drive; 1987-1989 GMC G1500, Main Drive; 1987-1989 GMC G2500, Main Drive; 1987-1989 GMC G3500, Main Drive; 1988-1989 GMC K1500, Main Drive; 1988-1989 GMC K2500, Main Drive; 1988-1989 GMC K3500, Main Drive; 1987-1989 GMC Safari, Main Drive; 1996-1998 Chevrolet Astro, Main Drive.

This part cross-references Gates K040685 and ACDelco 4K685 for the same application. The Dayco 5040685 is a direct-fit style serpentine belt for select Chevrolet Astro, GMC Safari, and GM truck platforms that use the listed main drive configuration.

What This Belt Helps Address

  • Squealing or chirping from a worn accessory drive belt
  • Cracking, glazing, or rib wear on the existing belt
  • Loss of proper drive to belt-driven accessories
  • Incorrect belt length on the specified GM main drive setup
  • Reduced belt stability in hot or cold operating conditions

Installation Notes and Tips

Verify the vehicle’s accessory layout before ordering, since this belt is listed for main drive applications without power steering, air pump, or air conditioning. Compare the old belt’s length, rib count, and section profile to the Dayco 5040685 before installation. Inspect pulleys and tensioner components for wear, contamination, or misalignment so the new belt can track correctly.

Quality Assurance

Dayco manufactures accessory drive components to SAE J1459 and SAE J2432 standards, and this belt uses EPDM with aramid reinforcement for consistent performance in demanding underhood conditions.

BrandDayco
Part Number5040685
MaterialEpdm, aramid reinforced
Top Width.54
ColorBlack
Effective Length1739.90
Effective Length68.50
Outside Circumference1754.13
Outside Circumference69.06
Rib Quantity4
Cross SectionK-section
Maximum Operating Temperature100
Maximum Operating Temperature212
Minimum Operating Temperature-42.7
Minimum Operating Temperature-45
Rib DepthStandard
Rib ProfileStraight rib
StandardsSae j1459, sae j2432

This part fits 113 vehicles. Search below:

YearMakeModelLitersCylindersPositionNotes
1998ChevroletAstroMain Drivew/o P.S., w/o A.P., w/o A.C.
1997ChevroletAstroMain Drivew/o P.S., w/o A.P., w/o A.C.
1996ChevroletAstroMain Drivew/o P.S., w/o A.P., w/o A.C.
1989ChevroletAstro4.3LV6Main Drivew/o P.S., w/o A.P., w/o A.C.
1989ChevroletC15004.3LV6Main Drivew/o P.S., w/o A.P., w/o A.C.
1989ChevroletC15005.7LV8Main Drivew/o P.S., w/o A.P., w/o A.C.
1989ChevroletC15005.0LV8Main Drivew/o P.S., w/o A.P., w/o A.C.
1989ChevroletC25004.3LV6Main Drivew/o P.S., w/o A.P., w/o A.C.
1989ChevroletC25005.7LV8Main Drivew/o P.S., w/o A.P., w/o A.C.
1989ChevroletC25005.0LV8Main Drivew/o P.S., w/o A.P., w/o A.C.
1989ChevroletC35005.7LV8Main Drivew/o P.S., w/o A.P., w/o A.C.
1989ChevroletG104.3LV6Main Drivew/o P.S., w/o A.P., w/o A.C.
1989ChevroletG105.7LV8Main Drivew/o P.S., w/o A.P., w/o A.C.
1989ChevroletG105.0LV8Main Drivew/o P.S., w/o A.P., w/o A.C.
1989ChevroletG204.3LV6Main Drivew/o P.S., w/o A.P., w/o A.C.
1989ChevroletG205.7LV8Main Drivew/o P.S., w/o A.P., w/o A.C.
1989ChevroletG205.0LV8Main Drivew/o P.S., w/o A.P., w/o A.C.
1989ChevroletG304.3LV6Main Drivew/o P.S., w/o A.P., w/o A.C.
1989ChevroletG305.7LV8Main Drivew/o P.S., w/o A.P., w/o A.C.
1989ChevroletK15004.3LV6Main Drivew/o P.S., w/o A.P., w/o A.C.
1989ChevroletK15005.7LV8Main Drivew/o P.S., w/o A.P., w/o A.C.
1989ChevroletK15005.0LV8Main Drivew/o P.S., w/o A.P., w/o A.C.
1989ChevroletK25004.3LV6Main Drivew/o P.S., w/o A.P., w/o A.C.
1989ChevroletK25005.7LV8Main Drivew/o P.S., w/o A.P., w/o A.C.
1989ChevroletK25005.0LV8Main Drivew/o P.S., w/o A.P., w/o A.C.
1989ChevroletK35005.7LV8Main Drivew/o P.S., w/o A.P., w/o A.C.
1989GMCC15004.3LV6Main Drivew/o P.S., w/o A.P., w/o A.C.
1989GMCC15005.7LV8Main Drivew/o P.S., w/o A.P., w/o A.C.
1989GMCC15005.0LV8Main Drivew/o P.S., w/o A.P., w/o A.C.
1989GMCC25004.3LV6Main Drivew/o P.S., w/o A.P., w/o A.C.
1989GMCC25005.7LV8Main Drivew/o P.S., w/o A.P., w/o A.C.
1989GMCC25005.0LV8Main Drivew/o P.S., w/o A.P., w/o A.C.
1989GMCC35005.7LV8Main Drivew/o P.S., w/o A.P., w/o A.C.
1989GMCG15004.3LV6Main Drivew/o P.S., w/o A.P., w/o A.C.
1989GMCG15005.7LV8Main Drivew/o P.S., w/o A.P., w/o A.C.
1989GMCG15005.0LV8Main Drivew/o P.S., w/o A.P., w/o A.C.
1989GMCG25004.3LV6Main Drivew/o P.S., w/o A.P., w/o A.C.
1989GMCG25005.7LV8Main Drivew/o P.S., w/o A.P., w/o A.C.
1989GMCG25005.0LV8Main Drivew/o P.S., w/o A.P., w/o A.C.
1989GMCG35004.3LV6Main Drivew/o P.S., w/o A.P., w/o A.C.
1989GMCG35005.7LV8Main Drivew/o P.S., w/o A.P., w/o A.C.
1989GMCK15004.3LV6Main Drivew/o P.S., w/o A.P., w/o A.C.
1989GMCK15005.7LV8Main Drivew/o P.S., w/o A.P., w/o A.C.
1989GMCK15005.0LV8Main Drivew/o P.S., w/o A.P., w/o A.C.
1989GMCK25004.3LV6Main Drivew/o P.S., w/o A.P., w/o A.C.
1989GMCK25005.7LV8Main Drivew/o P.S., w/o A.P., w/o A.C.
1989GMCK25005.0LV8Main Drivew/o P.S., w/o A.P., w/o A.C.
1989GMCK35005.7LV8Main Drivew/o P.S., w/o A.P., w/o A.C.
1989GMCSafari4.3LV6Main Drivew/o P.S., w/o A.P., w/o A.C.
1988ChevroletAstro4.3LV6Main Drivew/o P.S., w/o A.P., w/o A.C.
1988ChevroletC15004.3LV6Main Drivew/o P.S., w/o A.P., w/o A.C.
1988ChevroletC15005.7LV8Main Drivew/o P.S., w/o A.P., w/o A.C.
1988ChevroletC15005.0LV8Main Drivew/o P.S., w/o A.P., w/o A.C.
1988ChevroletC25004.3LV6Main Drivew/o P.S., w/o A.P., w/o A.C.
1988ChevroletC25005.7LV8Main Drivew/o P.S., w/o A.P., w/o A.C.
1988ChevroletC25005.0LV8Main Drivew/o P.S., w/o A.P., w/o A.C.
1988ChevroletC35005.7LV8Main Drivew/o P.S., w/o A.P., w/o A.C.
1988ChevroletG104.3LV6Main Drivew/o P.S., w/o A.P., w/o A.C.
1988ChevroletG105.7LV8Main Drivew/o P.S., w/o A.P., w/o A.C.
1988ChevroletG105.0LV8Main Drivew/o P.S., w/o A.P., w/o A.C.
1988ChevroletG204.3LV6Main Drivew/o P.S., w/o A.P., w/o A.C.
1988ChevroletG205.7LV8Main Drivew/o P.S., w/o A.P., w/o A.C.
1988ChevroletG205.0LV8Main Drivew/o P.S., w/o A.P., w/o A.C.
1988ChevroletG304.3LV6Main Drivew/o P.S., w/o A.P., w/o A.C.
1988ChevroletG305.7LV8Main Drivew/o P.S., w/o A.P., w/o A.C.
1988ChevroletK15004.3LV6Main Drivew/o P.S., w/o A.P., w/o A.C.
1988ChevroletK15005.7LV8Main Drivew/o P.S., w/o A.P., w/o A.C.
1988ChevroletK15005.0LV8Main Drivew/o P.S., w/o A.P., w/o A.C.
1988ChevroletK25004.3LV6Main Drivew/o P.S., w/o A.P., w/o A.C.
1988ChevroletK25005.7LV8Main Drivew/o P.S., w/o A.P., w/o A.C.
1988ChevroletK25005.0LV8Main Drivew/o P.S., w/o A.P., w/o A.C.
1988ChevroletK35005.7LV8Main Drivew/o P.S., w/o A.P., w/o A.C.
1988GMCC15004.3LV6Main Drivew/o P.S., w/o A.P., w/o A.C.
1988GMCC15005.7LV8Main Drivew/o P.S., w/o A.P., w/o A.C.
1988GMCC15005.0LV8Main Drivew/o P.S., w/o A.P., w/o A.C.
1988GMCC25004.3LV6Main Drivew/o P.S., w/o A.P., w/o A.C.
1988GMCC25005.7LV8Main Drivew/o P.S., w/o A.P., w/o A.C.
1988GMCC25005.0LV8Main Drivew/o P.S., w/o A.P., w/o A.C.
1988GMCC35005.7LV8Main Drivew/o P.S., w/o A.P., w/o A.C.
1988GMCG15004.3LV6Main Drivew/o P.S., w/o A.P., w/o A.C.
1988GMCG15005.7LV8Main Drivew/o P.S., w/o A.P., w/o A.C.
1988GMCG15005.0LV8Main Drivew/o P.S., w/o A.P., w/o A.C.
1988GMCG25004.3LV6Main Drivew/o P.S., w/o A.P., w/o A.C.
1988GMCG25005.7LV8Main Drivew/o P.S., w/o A.P., w/o A.C.
1988GMCG25005.0LV8Main Drivew/o P.S., w/o A.P., w/o A.C.
1988GMCG35004.3LV6Main Drivew/o P.S., w/o A.P., w/o A.C.
1988GMCG35005.7LV8Main Drivew/o P.S., w/o A.P., w/o A.C.
1988GMCK15004.3LV6Main Drivew/o P.S., w/o A.P., w/o A.C.
1988GMCK15005.7LV8Main Drivew/o P.S., w/o A.P., w/o A.C.
1988GMCK15005.0LV8Main Drivew/o P.S., w/o A.P., w/o A.C.
1988GMCK25004.3LV6Main Drivew/o P.S., w/o A.P., w/o A.C.
1988GMCK25005.7LV8Main Drivew/o P.S., w/o A.P., w/o A.C.
1988GMCK25005.0LV8Main Drivew/o P.S., w/o A.P., w/o A.C.
1988GMCK35005.7LV8Main Drivew/o P.S., w/o A.P., w/o A.C.
1988GMCSafari4.3LV6Main Drivew/o P.S., w/o A.P., w/o A.C.
1987ChevroletAstro4.3LV6Main Drivew/o P.S., w/o A.P., w/o A.C.
1987ChevroletG104.3LV6Main Drivew/o P.S., w/o A.P., w/o A.C.
1987ChevroletG105.7LV8Main Drivew/o P.S., w/o A.P., w/o A.C.
1987ChevroletG105.0LV8Main Drivew/o P.S., w/o A.P., w/o A.C.
1987ChevroletG204.3LV6Main Drivew/o P.S., w/o A.P., w/o A.C.
1987ChevroletG205.7LV8Main Drivew/o P.S., w/o A.P., w/o A.C.
1987ChevroletG205.0LV8Main Drivew/o P.S., w/o A.P., w/o A.C.
1987ChevroletG304.3LV6Main Drivew/o P.S., w/o A.P., w/o A.C.
1987ChevroletG305.7LV8Main Drivew/o P.S., w/o A.P., w/o A.C.
1987GMCG15004.3LV6Main Drivew/o P.S., w/o A.P., w/o A.C.
1987GMCG15005.7LV8Main Drivew/o P.S., w/o A.P., w/o A.C.
1987GMCG15005.0LV8Main Drivew/o P.S., w/o A.P., w/o A.C.
1987GMCG25004.3LV6Main Drivew/o P.S., w/o A.P., w/o A.C.
1987GMCG25005.7LV8Main Drivew/o P.S., w/o A.P., w/o A.C.
1987GMCG25005.0LV8Main Drivew/o P.S., w/o A.P., w/o A.C.
1987GMCG35004.3LV6Main Drivew/o P.S., w/o A.P., w/o A.C.
1987GMCG35005.7LV8Main Drivew/o P.S., w/o A.P., w/o A.C.
1987GMCSafari4.3LV6Main Drivew/o P.S., w/o A.P., w/o A.C.

* 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:

4K685

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

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