PPE Duramax Thermostat Housing Cover. Rust is the enemy of your coolant system. Upgrade your rusty OEM thermostat housing cover with a Cast 304 Stainless Steel Thermostat Housing Cover from PPE. This direct bolt-on replacement adds style and function to your engine bay. The stainless steel material is corrosion and rust-resistant.

We've engineered an easy way of bleeding off air from your coolant system by adding our Black Anodized Aluminum Bleeder Screw with a built-in air channel and a Viton O-ring. This makes quick work of purging air from your system without removing the entire screw. Just turn, purge and tighten.