Wehrli Transmission Cooler Thermostat Bypass Plug WCF100469 For 17-19 L5P Duramax Transmission Cooler Thermostat Bypass Plug WCF100469 For 17-19 L5P Duramax - CNC Machined Billet Aluminum Thermostatic Bypass Plug- Black Anodized Finish- High temperature silicone O-ring seals-... MSRP: Was: Now: $56.00 Add to Cart The item has been added