Wehrli Custom Fab Billet Coolant Heater Core Firewall Fitting for Select GM 1999-2023 (WCF100155)

Fits select 1999-2023 GM vehicles including Chevrolet Silverado and GMC Sierra 1500, 2500 HD, 3500 HD, Suburban, Tahoe, Yukon, Cadillac Escalade, and Hummer H2.

The factory plastic heater core firewall fitting is a notorious failure point on GM trucks and SUVs, often becoming brittle and cracking due to constant heat cycles and engine vibration. This Wehrli Custom Fabrication (WCF) billet aluminum fitting provides a permanent, professional-grade solution. This direct-fit upgrade replaces the fragile OEM plastic component with a precision-machined part designed to handle high cooling system pressures without the risk of sudden failure.

Each fitting is CNC-machined from high-grade aluminum and features a 5/8" hose barb and a double O-ring seal to ensure a positive, leak-free connection at the firewall. The clear anodized finish adds an extra layer of protection against corrosion, making it an essential cooling system upgrade for both Duramax diesel and gasoline GM engines.

• Manufacturer Part Number: WCF100155
• Replaces GM/AC Delco Part Number: 15032062
• Material: CNC-machined billet aluminum
• Finish: Clear anodized for superior corrosion resistance
• Connection: 5/8" hose barb
• Sealing: Double O-ring design for maximum leak protection
• Installation: Easy direct-fit replacement for the factory plastic fitting
• Origin: Made in the USA