
Coolant Bypass Tube - Water Pump to Thermostat Housing 2011-2016 GM 6.6L Duramax LML Pacific Performance Engineering
The OEM mild steel tube is prone to rust, which can lead to coolant system contamination and eventual leaks. Over time, factory O-rings also tend to harden and lose compression, increasing the risk of failure. PPE's upgraded bypass tube is specifically designed to work with the factory water pump
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The OEM mild steel tube is prone to rust, which can lead to coolant system contamination and eventual leaks. Over time, factory O-rings also tend to harden and lose compression, increasing the risk of failure. PPE's upgraded bypass tube is specifically designed to work with the factory water pump and is crafted from high-grade 304 stainless to prevent corrosion and ensure reliable, long-term performance.
OEM PN for Reference:
GM 12633704 Features: Coolant Bypass Tube
- Water Pump to Thermostat Housing 2011-2016 GM 6.6L Duramax LML Polished 304 stainless steel Hydroformed for exact fitment Comes with both upper and lower O-rings 1 Year Warranty






