Western Star Radiator - Western Star 3A0582030003, Northern Radiator 238769, Active Radiator Supply Company 800121, Reach Cooling 42-10477

When your Western Star 4900 Series needs a new radiator, the Reach Cooling 42-10477 delivers a dependable aftermarket replacement built to meet or exceed OE specifications. This direct-fit unit replaces Western Star 3S011727 - the factory reference number - along with Northern Radiator 238769, Active Radiator Supply Company 800121, 1-800-Radiator 2401240, Serck FLA001513, and Paccar Parts RAD42-10477TRP, making it straightforward to confirm you have the right part before it ever hits your shop floor. Fitment covers the Western Star 4900EX, 4900FA, and 4900SA from 2008 through 2011 across a broad range of engine configurations. The aluminum core and plastic tank construction uses a down-flow design, and the unit includes an integrated transmission oil cooler with fittings spaced 12 inches apart. Reach Cooling reinforces durability throughout: B-type tubes with central reinforcement resist pressure, deep extrusion headers strengthen the tube-to-header joint against vibration and thermal cycling, folded fin edges improve heat dissipation, and thermal expansion cuts reduce core fatigue over time. Longer header tabs add further resistance to tank-to-header leaks. If you are cross-referencing by the OEM number 3S011727 or any of the listed interchanges, the Reach Cooling 42-10477 is the confirmed aftermarket replacement for your Western Star 4900EX, 4900FA, or 4900SA.