{"product_id":"bsnovt-radiator-overflow-hose-coolant-bypass-line-for-audi-a4-a5-2017-2021-direct-oem-fit-8w0121081an-heat-resistant","title":"BSNOVT Radiator Overflow Hose Coolant Bypass Line for Audi A4\/A5 2017–2021 — Direct OEM Fit 8W0121081AN, Heat-Resistant","description":"\u003cp\u003e\u003cstrong\u003eBSNOVT Radiator Overflow Hose is a direct replacement coolant bypass line built to replace OEM 8W0121081AN for select Audi A4 and A5 models, channeling excess coolant to the expansion tank to protect engine temperature balance.\u003c\/strong\u003e\u003c\/p\u003e\n\n\u003cp\u003eDesigned for Audi owners and mechanics who need a reliable coolant transfer line, this BSNOVT hose restores proper overflow flow and helps maintain the cooling system’s integrity after the original line fails or is removed. Built from heat-resistant materials, the hose fits specific Audi A4 and A5 variants and arrives ready to install as a single-piece replacement.\u003c\/p\u003e\n\n\u003ch3\u003eWhich Audi models does this overflow hose fit?\u003c\/h3\u003e\n\u003cp\u003eThis BSNOVT radiator overflow hose is made to match the fitment and routing of the original amplifier for certain 2017–2021 Audi A4 and A5 vehicles. Confirm compatibility with your VIN or service manual before purchase to ensure correct fit and performance.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eCompatible with Audi A4 (2017–2020) and A4 Quattro (2017–2021)\u003c\/li\u003e\n  \u003cli\u003eFits Audi A4 allroad (2017–2020)\u003c\/li\u003e\n  \u003cli\u003eFits Audi A5 Quattro and A5 Sportback (2018–2020)\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eHow does this hose replace OEM part 8W0121081AN?\u003c\/h3\u003e\n\u003cp\u003eThe BSNOVT line is manufactured to replicate the OEM part’s shape, ports, and attachment points so it installs in the same routing as the original. That ensures a snug connection to the expansion tank and radiator system without need for aftermarket adapters.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eDirect replacement for part number 8W0121081AN\u003c\/li\u003e\n  \u003cli\u003eSame connection points and contours as the original component\u003c\/li\u003e\n  \u003cli\u003eShips as a single hose ready for straightforward swap-in installation\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eWhat materials and durability can I expect?\u003c\/h3\u003e\n\u003cp\u003eConstructed from high-temperature-resistant elastomers and reinforced sections, this coolant transfer line resists engine-bay heat and typical coolant exposure. The material selection aims to reduce swelling, softening, and premature cracking under normal operating conditions.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eHeat-resistant compound suitable for engine bay temperatures\u003c\/li\u003e\n  \u003cli\u003eReinforced areas to resist pressure and flexing\u003c\/li\u003e\n  \u003cli\u003eDesigned to minimize leaks and extend service life\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eHow easy is installation and what’s included?\u003c\/h3\u003e\n\u003cp\u003eThe product ships as one replacement hose so a mechanic or experienced DIYer can replace the old line without sourcing extra fittings. Basic tools are usually all that’s required and the hose follows the OEM routing for a clean install.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eIncludes one BSNOVT coolant overflow\/bypass hose\u003c\/li\u003e\n  \u003cli\u003eDirect-fit design to speed installation time\u003c\/li\u003e\n  \u003cli\u003eNo additional parts typically required—check clamps and seals during replacement\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cp\u003eWho is this for: This BSNOVT radiator overflow hose is intended for Audi A4 and A5 owners, independent repair shops, and DIY enthusiasts who need a dependable OEM-style replacement for part 8W0121081AN. Choose this hose if you want a heat-resistant, direct-fit coolant bypass line that restores proper overflow routing and helps prevent coolant loss after the original line becomes compromised.\u003c\/p\u003e\n\u003csection class=\"product-faq-snippet\"\u003e\u003ch3\u003eFAQ\u003c\/h3\u003e\n\u003cdiv class=\"faq-item\"\u003e\n\u003cp class=\"faq-q\"\u003eQ: Is this hose an exact fit for OEM part 8W0121081AN?\u003c\/p\u003e\n\u003cp class=\"faq-a\"\u003eA: Yes — the BSNOVT hose is designed as a direct replacement for OEM 8W0121081AN for the listed Audi models.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"faq-item\"\u003e\n\u003cp class=\"faq-q\"\u003eQ: Do I need extra parts to install this hose?\u003c\/p\u003e\n\u003cp class=\"faq-a\"\u003eA: Usually no; it includes one direct-fit hose, but inspect or replace clamps and seals as needed during installation.\u003c\/p\u003e\n\u003c\/div\u003e\u003c\/section\u003e","brand":"BSNOVT","offers":[{"title":"Default Title","offer_id":48085353037982,"sku":"B0DRVBNJ66","price":40.87,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0781\/2041\/9486\/files\/bsnovt-radiator-overflow-hose-front-view.jpg?v=1785869979","url":"https:\/\/northtrailauto.ca\/products\/bsnovt-radiator-overflow-hose-coolant-bypass-line-for-audi-a4-a5-2017-2021-direct-oem-fit-8w0121081an-heat-resistant","provider":"North Trail Auto","version":"1.0","type":"link"}