LS and LT Swap Radiator with Auto Trans Fans for 1963-1966 GM C/K Trucks
Swapping an LS or LT engine into a 1963 through 1966 C/K truck exposes cooling and transmission demands that stock radiators cannot meet and the 1963-1966 GM Truck Radiator (Auto Trans) with Fans steps in to keep coolant and transmission fluid at optimal levels under tow and in traffic. It features a precision TIG welded aluminum core and an integrated transmission cooler port that aligns with factory fittings for neat hose routing and consistent heat rejection across the entire surface. Dual electric fans engage automatically via fluid sensors to maintain steady airflow, preventing thermal spots during low speed runs or steep climbs, and installation is quick since the radiator bolts directly to original C and K frame brackets with no trimming or drilling required.
Precision TIG Welded Aluminum for Structural Integrity
The radiator core and side tanks are joined by full TIG welds that melt the base aluminum into a single unified assembly without added filler material. This process preserves consistent wall thickness from inlet to outlet, ensuring even heat transfer and eliminating zones prone to stress fractures or leaks. Fabricated in the USA, the aluminum construction resists corrosion and reduces overall mass, easing load on the frame while retaining high strength. During repeated heating and cooling cycles, the continuous weld seams prevent seal fatigue and maintain core integrity under tow or in slow traffic. The result is a maintenance friendly cooler built to withstand decades of demanding use without sacrifice in performance or reliability.
Seamless Transmission Cooler Port for Optimal Fluid Management
This radiator integrates a purpose-built port for automatic transmission fluid that aligns precisely with factory hose fittings for a direct connection. By matching the original location, it eliminates sharp bends or twists that could restrict flow and create hot spots in the line. The design also reduces hose wear from chafing, simplifying routine inspections and service access when replacing or upgrading lines. With minimal plumbing losses, fluid pressure and temperature remain steady even under heavy load or steep grades. Consistent fluid flow translates to stable transmission temperatures and extended component life, whether towing a trailer or creeping through city traffic.
Responsive Dual Electric Fan System for Consistent Cooling
An engine coolant sensor and a transmission fluid switch work in tandem to trigger the pair of electric fans when temperatures climb. Each fan covers half the radiator's face for complete airflow distribution, preventing thermal pockets that can form in the core. The low amp draw design ensures the fans spin up before natural airflow can catch up at low speed, protecting both engine and trans components from heat soak. By cutting on automatically, the system delivers exactly the right amount of airflow needed to keep coolant and fluid inside safe ranges. This intelligent fan control extends service intervals and safeguards internal parts against premature wear caused by excessive heat.
Finish Selections for Protection and Heat Rejection
Choose the classic bare aluminum option to maximize direct conductivity of core metal for rapid heat dissipation. Alternatively, the black epoxy coat resists moisture, road salt, and surface abrasion while still allowing effective thermal transfer. Masking during application preserves precise bracket and port clearances to guarantee a perfect fit with original C and K frame mounts. Both finishes remain easy to clean with mild detergents and retain structural integrity over time. This attention to surface treatment ensures corrosion defense and engine bay aesthetics without compromising cooling efficiency.
This radiator provides steady cooling for LS and LT swaps under load or in stop and go traffic. For the same radiator but without fans see our 1963-1966 GM Truck Radiator Automatic Transmission.