Extended Length LS Cool ant / Water Temperature

The ICT Billet Extended Length LS Coolant/Water Temperature Fitting (SKU ICT551179L) is a precision adapter designed for custom coolant line routing in LS-platform engine builds. This straight-fitting adapter converts a 3/8-18 female port to accept 12mm x 1.50 male threads with O-ring sealing, making it ideal for water temperature sensor installations, coolant bypass circuits, and auxiliary cooling system integrations where factory port spacing or thread patterns don't align with aftermarket component requirements.

Manufactured from steel with zinc oxide plating, this fitting offers corrosion resistance critical in high-heat engine bays where coolant spray and thermal cycling accelerate oxidation. The O-ring seal design eliminates the need for thread sealant tape, reducing installation complexity and ensuring a leak-free connection under pressure cycling—particularly important in forced-induction or high-boost applications where coolant system integrity directly impacts engine reliability. Weighing just 0.09 lbs and measuring 5.15 inches in length, the extended design provides clearance in tight engine compartments and custom fabrication scenarios where standard adapters interfere with headers, turbo manifolds, or fuel system components.

Engine builders, performance tuners, and LS swap specialists rely on precision fittings like this one to solve port mismatch problems without custom welding or exotic solutions. This adapter bridges common thread-size gaps between OEM cooling passages and aftermarket sensor housings, turbo coolant feeds, and remote mounting plates—essential when transitioning between generations of LS variants (5.3L, 6.0L, 6.2L, LT1, LT4) or mixing components from different manufacturers. Its straightforward geometry and proven O-ring design make it a dependable reference solution for anyone completing a serious LS build or upgrading factory cooling architecture.