{"product_id":"mmx-performance-bmw-billet-coolant-expansion-cap","title":"MMX Performance BMW Billet Coolant Expansion Cap","description":"\u003cp\u003eThe MMX Performance BMW Billet Coolant Expansion Cap is a precision-engineered upgrade designed to improve both the durability and appearance of your BMW’s cooling system. Unlike decorative covers, this is a true OE replacement cap that fully replaces the factory plastic unit while retaining complete factory functionality.\u003c\/p\u003e\n\u003cp\u003eFactory coolant caps are constructed from plastic and can degrade over time due to repeated heat cycles, leading to potential sealing issues and reduced confidence during servicing. The MMX billet cap addresses this with a robust construction machined from a solid block of 6061 aerospace-grade aluminum, offering superior strength, heat resistance, and long-term reliability.\u003c\/p\u003e\n\u003cp\u003eEach cap is CNC-machined using advanced 5-axis technology, then finished in a deep gloss black anodizing for a clean OEM+ appearance and excellent corrosion resistance. The carefully machined exterior provides improved grip, allowing for confident installation and removal during coolant servicing.\u003c\/p\u003e\n\u003cp\u003ePre-installed with OE-spec internals including a pressure valve, internal spring, and Viton O-ring seal, the MMX coolant expansion cap ensures proper pressure regulation and sealing performance without requiring any transfer of components from the factory cap. This makes installation simple and fully plug-and-play.\u003c\/p\u003e\n\u003cp\u003eAvailable in both 60mm and 90mm fitments, this billet coolant cap replaces BMW OE part numbers 17117639024 (60mm) and 17117639021 (90mm). Please confirm the part number on the underside of your existing cap to ensure correct fitment.\u003c\/p\u003e\n\u003cp\u003eA functional and aesthetic upgrade, the MMX Performance BMW Billet Coolant Expansion Cap delivers long-term reliability while adding a refined finishing touch to any engine bay.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eProduct Details\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eMMX Performance billet coolant expansion cap for BMW\u003c\/li\u003e\n\u003cli\u003eAvailable in 60mm and 90mm fitments\u003c\/li\u003e\n\u003cli style=\"font-weight: bold;\"\u003e\u003cstrong\u003eReplaces OE part numbers 17117639024 (60mm) and 17117639021 (90mm)\u003c\/strong\u003e\u003c\/li\u003e\n\u003cli\u003eDirect OE replacement with full factory-style internals\u003c\/li\u003e\n\u003cli\u003ePre-installed pressure valve, internal spring, and Viton O-ring seal\u003c\/li\u003e\n\u003cli\u003eCNC-machined from 6061 aerospace-grade aluminum\u003c\/li\u003e\n\u003cli\u003eAdvanced 5-axis machining for precise fitment\u003c\/li\u003e\n\u003cli\u003eGloss black anodized finish for corrosion resistance and OEM+ appearance\u003c\/li\u003e\n\u003cli\u003eImproved grip design for easier installation and removal\u003c\/li\u003e\n\u003cli\u003eEliminates concerns associated with aging plastic caps\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cstrong\u003eVehicle Applications\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eRecommended Products\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003e\u003ca href=\"https:\/\/ind-distribution.com\/products\/mmr-performance-bmw-billet-oil-filler-cap-s58-b48e?pr_prod_strat=pinned\u0026amp;pr_rec_id=2118c418e\u0026amp;pr_rec_pid=7811578364100\u0026amp;pr_ref_pid=7811620798660\u0026amp;pr_seq=uniform\" target=\"_blank\"\u003eMMX Performance BMW Billet Oil Filler Cap – S58 \/ B48E\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca href=\"https:\/\/ind-distribution.com\/products\/mmr-performance-bmw-billet-oil-filler-cap?pr_prod_strat=pinned\u0026amp;pr_rec_id=2118c418e\u0026amp;pr_rec_pid=7365956894916\u0026amp;pr_ref_pid=7811620798660\u0026amp;pr_seq=uniform\" target=\"_blank\"\u003eMMX Performance BMW Billet Oil Filler Cap\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cstrong\u003eNotes\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eBMW models equipped with matching OE coolant cap part numbers\u003c\/li\u003e\n  \u003cli\u003eSKU: MMR03-1502 (90mm), MMR03-1503 (60mm)\u003c\/li\u003e\n  \u003cli\u003eDirect OE replacement – no modifications required\u003c\/li\u003e\n  \u003cli\u003eVerify cap size or OE part number prior to purchase\u003c\/li\u003e\n  \u003cli\u003eProlonged exposure to extreme heat may affect anodized finish appearance\u003c\/li\u003e\n  \u003cli\u003eThis does not impact performance or functionality\u003cbr\u003e\n\u003c\/li\u003e\n  \u003cli\u003eIncludes a 1-year manufacturer warranty against defects in materials and workmanship\u003c\/li\u003e\n  \u003cli\u003eDesigned and tested in the United Kingdom\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"IND Distribution","offers":[{"title":"90mm Cap (Replaces OE Part 17117639021) | MMR03-1502","offer_id":47411626606786,"sku":"MMR03-1502","price":127.7,"currency_code":"USD","in_stock":true},{"title":"60mm Cap (Replaces OE Part 17117639024) | MMR03-1503","offer_id":47411626639554,"sku":"MMR03-1503","price":127.7,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0737\/0784\/7874\/files\/mmx-bmw-billet-coolant-expansion-cap-90mm-black-anodized-white-background.jpg?v=1776276701","url":"https:\/\/grocerygetterperformance.com\/products\/mmx-performance-bmw-billet-coolant-expansion-cap","provider":"Grocery Getter Performance","version":"1.0","type":"link"}