{"product_id":"koyorad-a13903-radiator","title":"Koyorad A13903 Radiator","description":"\u003ch2\u003eOE Equivalent Radiator Replacement\u003c\/h2\u003e\u003cp\u003eThe Koyorad A13903 radiator is an OE equivalent replacement built for direct cooling-system service. It is engineered to match the original-style fit and core dimensions needed for a proper radiator replacement on select BMW applications.\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eOE equivalent radiator from Koyorad\u003c\/li\u003e\n\u003cli\u003eCore dimensions: 615 mm height, 604.8 mm width, and 25 mm thickness\u003c\/li\u003e\n\u003cli\u003eUpper and lower tank measurements support original-style cooling system packaging\u003c\/li\u003e\n\u003cli\u003eFits 2018-2019 BMW X3 and 2019 BMW X4\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eDetailed Fitment and Design\u003c\/h2\u003e\u003cp\u003eUse the Koyorad A13903 when replacing a worn or leaking radiator on a BMW X3 or BMW X4 with the listed fitment. The radiator core and tank dimensions are specified to align with OE-style cooling system layout, helping maintain proper space, hose connection, and thermal management requirements. This part cross-references Dorman - HELP 13903 for the same application.\u003c\/p\u003e\u003ch2\u003eCommon Replacement Reasons\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003eCoolant leaks from a damaged radiator core or tank\u003c\/li\u003e\n\u003cli\u003eOverheating caused by restricted coolant flow\u003c\/li\u003e\n\u003cli\u003eCorrosion or age-related deterioration in the cooling system\u003c\/li\u003e\n\u003cli\u003ePhysical damage from road debris or impact\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eInstallation Notes\u003c\/h2\u003e\u003cp\u003eVerify radiator dimensions, hose connections, and mounting points against the original unit before installation. Drain and refill the cooling system with the correct coolant specification, then bleed air from the system according to factory service procedures. Confirm fan operation and inspect for leaks after installation.\u003c\/p\u003e\u003ch2\u003eQuality Assurance\u003c\/h2\u003e\u003cp\u003eKoyorad states that its radiators are OE equivalent replacements backed by the company’s technical manufacturing experience. Part number A13903 is built for direct replacement service on the listed BMW applications.\u003c\/p\u003e","brand":"Koyorad","offers":[{"title":"Default Title","offer_id":53526611656885,"sku":"GTQS-A13903","price":200.66,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0628\/1442\/1173\/files\/KO_A13903_Dia.jpg?v=1792048549","url":"https:\/\/www.partcatalog.com\/products\/koyorad-a13903-radiator","provider":"PartCatalog","version":"1.0","type":"link"}