Wehrli WCF100699 GM Billet Heater Core Fitting Kit with Hose Replace OEM 1/2 in

Vehicle Fitment

• Universal - Preformed 1/2 in. heater hose assembly designed for GM full-size trucks and SUVs equipped with a 1/2 in. quick-connect heater core fitting. Primarily designed for GM Silverado and Sierra platforms including 2001-2022 model years across 1500, 2500HD, and 3500HD configurations. Compatible with all 6.6L Duramax generations (LB7, LLY, LBZ, LMM, LML, L5P) and select non-diesel GM full-size truck applications using the same OEM heater core fitting style.

Fitment Notes

• This is a universal preformed 1/2 in. heater hose assembly. Verify that your vehicle uses a 1/2 in. quick-connect style heater core fitting before purchase.
• Replaces OEM/AC Delco heater hose connector part numbers such as 15032062 and Dorman 800-409.
• Compatible with all 6.6L Duramax generations: 2001-2004 LB7, 2004.5-2005 LLY, 2006-2007 LBZ, 2007.5-2010 LMM, 2011-2016 LML, and 2017+ L5P.
• Also compatible with GM half-ton Silverado/Sierra 1500 (1999-2022) and other full-size GM trucks and SUVs using the same OEM quick-connect heater core fitting style.
• Individual trim, build date, and factory option variations may affect fitment. Verify against your specific vehicle before installation.

Features

• CNC-machined billet aluminum quick-connect fitting permanently eliminates the failure-prone OEM plastic fitting that cracks, becomes brittle, and leaks with age and heat cycling
• Preformed 1/2 in. heater hose assembly - arrives pre-shaped for direct installation without cutting or reforming
• Serviceable O-ring seals inside the billet fitting for easy maintenance and long-term reliability - no need to replace the entire assembly if seals wear
• Wire retainer clip connection design allows removal and reinstallation without special tools - a significant improvement over the OEM press-fit plastic design
• Hose construction exceeds OEM specification for improved burst strength and heat resistance
• Billet aluminum fitting provides superior resistance to heat, vibration, and coolant degradation compared to factory plastic
• Made in the USA by Wehrli Custom Fabrication (WCFab) in DeKalb, Illinois

Specifications

• Part Number: WCF100699
• Brand: Wehrli Custom Fabrication (WCFab)
• Fitting Material: Billet Aluminum
• Hose Type: Preformed 1/2 in. Heater Hose Assembly
• Hose Inner Diameter: 1/2 in.
• Connection Style: Quick-Connect with Wire Retainer Clip
• Seal Type: Serviceable O-rings
• Replaces: OEM/AC Delco 15032062, Dorman 800-409
• Shipping Weight: 2.0 lbs
• Package Dimensions: 6 in. x 6 in. x 4 in.
• Fitment Type: Universal (GM full-size trucks with 1/2 in. quick-connect heater core fitting)
• Country of Origin: USA (DeKalb, Illinois)

Included Components

• 1x WCF100699 Preformed 1/2 in. Heater Hose Assembly
• 1x Billet Aluminum Quick-Connect Heater Core Fitting
• 1x Wire Retainer Clip
• Serviceable O-ring seals (installed in billet fitting)

Product Description

The Wehrli Custom Fabrication WCF100699 is a preformed 1/2 in. heater hose assembly with a CNC-machined billet aluminum quick-connect fitting designed to replace the factory plastic heater core fitting on GM full-size trucks - a well-documented failure point across the full range of GMT800, GMT900, and K2XX platform vehicles including 2001-2022 Silverado and Sierra trucks with all 6.6L Duramax generations (LB7 through L5P) and select half-ton applications. The OEM plastic fitting is notorious for becoming brittle over time from sustained heat and coolant exposure, eventually cracking and causing coolant leaks that range from minor seeping to complete heater hose separation - a situation that can lead to rapid coolant loss and potential overheating. The WCF100699 permanently eliminates this failure point by replacing the plastic fitting with a precision-machined billet aluminum unit built to outlast the truck.

The billet aluminum fitting uses serviceable O-ring seals for a leak-proof, long-term connection that can be maintained without replacing the entire assembly. The wire retainer clip connection design mirrors the OEM quick-connect system for intuitive installation and removal without special tools - a critical convenience when accessing the heater core fitting in the tight confines of a full-size diesel engine bay. The preformed hose arrives pre-shaped to match the factory routing, eliminating the need for cutting, measuring, or reforming. Hose construction exceeds OEM burst strength and heat resistance specifications for added confidence in demanding towing, hauling, and performance applications.

WCFab describes this as a universal preformed heater hose assembly - it is designed to fit the standard 1/2 in. quick-connect heater core fitting style used across a broad range of GM full-size trucks and SUVs. Verify that your vehicle uses the same fitting style before ordering. Designed, machined, and assembled in the USA at WCFab's DeKalb, Illinois facility. Replaces OEM/AC Delco part 15032062 and Dorman part 800-409.