1999-2023 GM Billet Coolant Heater Core Firewall Fitting

Stop the heater core fitting leak

The plastic factory heater core firewall coolant fitting is a known failure point on Duramax trucks and other GM vehicles. Wehrli's direct-fit billet aluminum replacement stands up better to heat and vibration.

It has a 5/8 in. barb, a double O-ring seal and a clear anodized finish against corrosion. It installs easily and is made in the USA.

Who it's for

GM truck owners with a cracked or leaking heater core fitting, or who want to prevent one.

Key specs (per Wehrli)

What's included

• Billet heater core firewall fitting

Fitment notes

• Fits 2001-2023 Chevrolet Silverado / GMC Sierra 2500 / 3500 HD with the 6.6L Duramax.
• Wehrli also lists Escalade, Avalanche, Express / Savana, Kodiak, Silverado / Sierra 1500 and gas 2500 / 3500, Suburban, Tahoe, Yukon and Hummer H2 in various years; we list it for the Duramax trucks.
• Replaces GM / AC Delco 15032062 and Dorman 800-409.

Professional install available at Powertech Diesel, Idaho Falls — call 208-542-7793.