Eliminate the obstructive factory coolant hose routing on your 2001-2005 GM 6.6L Duramax with the HSP LB7/LLY Billet Thermostat Housing Kit With Coolant Return. With a CNC billet aluminum construction, this upper housing thermostat kit makes extra room for larger drop-in turbos in the valley as well as dual cp3 setups by eliminating the factory coolant hose that crosses over the driver side valve cover. HSP utilizes reinforced silicone boots and a hard tube for added strength versus the factory rubber hose. This kit features provisions to return coolant from the turbocharger.
Features:
- Reinforced Silicone Boots
- Includes Installation Hardware
- Allows Room For Dual CP3 Kits
- CNC Billet Aluminum Upper Thermostat Housing
- Improved Design Allows Easier Access To Driver Valve Cover
Note: For use with stock or drop-in replacement VGT turbos.
NOT FOR SALE IN THE STATE OF CALIFORNIA
Prop 65 
WARNING: Cancer & Reproductive Harm - P65Warnings.ca.gov