{"product_id":"180-thermostat-3974823-5292708-for-cummins-5-9l-isb-4-5l-qsb-b-series-engines","title":"180℉ Thermostat 3974823 5292708 for Cummins 5.9L ISB 4.5L QSB B-Series Engines","description":"\u003ch2\u003e180°F Thermostat for Cummins 5.9L ISB, 4.5L QSB, B-Series Engines\u003c\/h2\u003e\u003cp\u003eThis 180°F thermostat, with cross-reference numbers 3974823 and 5292708, is a direct replacement for Cummins 5.9L ISB, 4.5L QSB, and B-Series engines, ensuring proper engine operating temperature for efficient combustion and heating performance.\u003c\/p\u003e\u003ch4\u003eOverview\u003c\/h4\u003e\u003cp\u003eThis 180°F thermostat controls coolant flow to keep your Cummins 5.9L ISB, 4.5L QSB, or B-Series engine at its optimal operating temperature. It opens at 180°F to allow coolant circulation once the engine warms up, supporting efficient fuel burn, faster cab heat, and reduced engine wear. This thermostat is built for engines that specify a 180°F opening temperature, matching the original 3974823 and 5292708 part numbers.\u003c\/p\u003e\u003ch4\u003eBuilt For Performance\u003c\/h4\u003e\u003cul\u003e\n\u003cli\u003ePrecise 180°F opening temperature to match OEM specifications\u003c\/li\u003e\n\u003cli\u003eCross-references OEM numbers 3974823 and 5292708\u003c\/li\u003e\n\u003cli\u003eEngineered for Cummins 5.9L ISB, 4.5L QSB, and B-Series applications\u003c\/li\u003e\n\u003cli\u003eConstructed with durable metal and heat-resistant components for long service life\u003c\/li\u003e\n\u003cli\u003eEnsures consistent coolant flow for stable engine temperatures\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch4\u003eFits These Machines\u003c\/h4\u003e\u003cul\u003e\n\u003cli\u003efor Cummins 5.9L ISB\u003c\/li\u003e\n\u003cli\u003efor Cummins 4.5L QSB\u003c\/li\u003e\n\u003cli\u003efor Cummins B-Series engines\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch4\u003eOn-The-Job Use\u003c\/h4\u003e\u003cul\u003e\n\u003cli\u003eIdeal for replacing a stuck-open or stuck-closed thermostat during routine cooling system maintenance\u003c\/li\u003e\n\u003cli\u003eUsed in trucks, buses, agricultural equipment, and industrial machinery powered by these Cummins engines\u003c\/li\u003e\n\u003cli\u003eHelps restore proper warm-up time and heater output in cold climates\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch4\u003eSpecs At A Glance\u003c\/h4\u003e\u003ctable\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eOpening Temperature\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e180°F (82°C)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003ePart Number(s)\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e3974823, 5292708\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eEngine Family\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003efor Cummins 5.9L ISB, 4.5L QSB, B-Series\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\u003ch4\u003eGood To Know\u003c\/h4\u003e\u003cp\u003e\u003cstrong\u003eQ:\u003c\/strong\u003e What does a 180°F thermostat do? \u003cstrong\u003eA:\u003c\/strong\u003e It opens at 180°F to let coolant flow through the radiator, preventing engine overheating while allowing quick warm-up. This helps maintain proper combustion temperatures and reduces engine wear.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eQ:\u003c\/strong\u003e How do I know if this thermostat fits my engine? \u003cstrong\u003eA:\u003c\/strong\u003e Check your engine's serial number and existing part number against 3974823 or 5292708. Always confirm the thermostat diameter and opening temperature before installing.\u003c\/p\u003e\u003cp\u003e\u003cem\u003eSlight variation in finish or dimensions may occur between production runs, and fit can depend on serial number, so confirm compatibility before ordering.\u003c\/em\u003e\u003c\/p\u003e","brand":"Part Outfitters","offers":[{"title":"Default Title","offer_id":46624715473082,"sku":"ZZ3F01217","price":35.19,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0779\/2476\/1786\/files\/s-l1600_4e01fd3c-a840-42a7-97e9-ac12f07df428.jpg?v=1789151266","url":"https:\/\/partoutfitters.com\/products\/180-thermostat-3974823-5292708-for-cummins-5-9l-isb-4-5l-qsb-b-series-engines","provider":"Part Outfitters","version":"1.0","type":"link"}