{"product_id":"ngk-iridium-ix-spark-plugs-lfr5aix11-6-pack-fine-wire-iridium-14mm-thread-long-life","title":"NGK Iridium IX Spark Plugs LFR5AIX11 6-Pack — Fine-Wire Iridium, 14mm Thread, Long-Life","description":"\u003cp\u003e\u003cstrong\u003eNGK 4469 Iridium IX LFR5AIX11 spark plugs are high-performance, fine-wire iridium plugs designed to deliver more reliable ignition, improved throttle response, and long service life for compatible 6-cylinder engines.\u003c\/strong\u003e\u003c\/p\u003e\n\n\u003cp\u003eThese NGK Iridium IX plugs (Part No. LFR5AIX-11, Stock 4469) combine a durable iridium center tip with a taper-cut nickel ground electrode and a ceramic insulator to produce consistent sparks under demanding conditions. Built with a 0.044\" pre-gap (1.1 mm), 14.0 mm thread diameter, and a 26.5 mm reach, they suit a range of Hyundai, Infiniti, Kia, Nissan, Suzuki, and Toyota applications where precision ignition and longevity matter. The plugs include a crush washer and a non-removable nut electrical terminal for straightforward installation and secure connection.\u003c\/p\u003e\n\n\u003ch3\u003eHow do these NGK Iridium IX plugs improve everyday driving?\u003c\/h3\u003e\n\u003cp\u003eIridium’s fine-wire center electrode requires lower voltage to produce a focused spark, which helps the air\/fuel mixture ignite more completely. Drivers commonly notice steadier idle, crisper throttle response, and smoother acceleration after swapping to these plugs.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eFine-wire iridium center electrode for concentrated spark energy\u003c\/li\u003e\n  \u003cli\u003ePrecision laser-welded construction for uniform ignition\u003c\/li\u003e\n  \u003cli\u003e0.044\" pre-gap tuned for listed compatible engines\u003c\/li\u003e\n  \u003cli\u003eResistor design reduces radio frequency interference\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eWhat makes the LFR5AIX11 different from standard plugs?\u003c\/h3\u003e\n\u003cp\u003eUnlike conventional copper or platinum plugs, these NGK Iridium IX units use a hard iridium tip on a copper core, blending heat transfer with a wear-resistant electrode. The taper-cut ground electrode and J-gap layout optimize flame travel and combustion efficiency without changing factory ignition components.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eIridium tip on copper core balances durability and conductivity\u003c\/li\u003e\n  \u003cli\u003eTaper-cut ground electrode improves flame propagation\u003c\/li\u003e\n  \u003cli\u003eMid projection center electrode preserves combustion chamber geometry\u003c\/li\u003e\n  \u003cli\u003eFlat seat and 5\/8\" (16 mm) hex for common socket sizes\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eAre these plugs easy to install and maintain?\u003c\/h3\u003e\n\u003cp\u003eInstallation is straightforward for anyone with basic mechanical tools: they use a standard 14.0 mm thread and include a crush washer for seat sealing. They are engineered for long intervals between changes, helping reduce routine maintenance when matched to the recommended service schedule.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eReach: 1.043\" (26.5 mm) — confirm compatibility before fitting\u003c\/li\u003e\n  \u003cli\u003eCrush washer included for proper sealing on flat-seat engines\u003c\/li\u003e\n  \u003cli\u003eHex size 5\/8\" (16 mm) fits common spark plug sockets\u003c\/li\u003e\n  \u003cli\u003eResistor type helps protect vehicle electronics and reduces interference\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eWhich vehicles are these NGK LFR5AIX11 plugs compatible with?\u003c\/h3\u003e\n\u003cp\u003eNGK provides a broad compatibility list for many 6-cylinder engines across several manufacturers; check build dates and engine displacement before ordering. They match many Hyundai, Infiniti, Kia, Nissan, Suzuki, and Toyota models that require a 14 mm thread, 26.5 mm reach, and a 0.044\" gap.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eHyundai Genesis (2009 3.8L before 5\/1\/2008) and Santa Fe (2007–2009 2.7L)\u003c\/li\u003e\n  \u003cli\u003eInfiniti FX35, G35, I35, M35 and QX4 3.5L 6-cylinder years listed\u003c\/li\u003e\n  \u003cli\u003eNissan 350Z, Altima, Maxima, Murano, Frontier, Pathfinder, NV series, Quest, Xterra\u003c\/li\u003e\n  \u003cli\u003eToyota 4Runner, FJ Cruiser, Tundra models from 6\/2013 onward; Kia and Suzuki models listed\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cp\u003eWho is this for: drivers, technicians, and performance-minded owners seeking a durable, high-energy spark plug that fits many naturally aspirated and turbocharged 6-cylinder engines. If you want reduced misfire risk, more consistent starts, and extended plug life compared with standard copper plugs, the NGK 4469 Iridium IX LFR5AIX11 six-pack is built for those upgrades. Always verify engine compatibility, thread size, and reach against your vehicle’s service manual before installation.\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: What is the correct gap for NGK LFR5AIX11 plugs?\u003c\/p\u003e\n\u003cp class=\"faq-a\"\u003eA: These plugs come pre-set to a 0.044\" (1.1 mm) gap, suitable for the listed compatible engines.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"faq-item\"\u003e\n\u003cp class=\"faq-q\"\u003eQ: How long do NGK Iridium IX plugs typically last?\u003c\/p\u003e\n\u003cp class=\"faq-a\"\u003eA: Iridium IX plugs are engineered for extended service life compared with copper plugs; follow your vehicle’s maintenance interval for replacement guidance.\u003c\/p\u003e\n\u003c\/div\u003e\u003c\/section\u003e","brand":"NGK","offers":[{"title":"Default Title","offer_id":48084155072670,"sku":"B00330AMYS","price":73.89,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0781\/2041\/9486\/files\/ngk-4469-front-packaging.jpg?v=1785847632","url":"https:\/\/northtrailauto.ca\/products\/ngk-iridium-ix-spark-plugs-lfr5aix11-6-pack-fine-wire-iridium-14mm-thread-long-life","provider":"North Trail Auto","version":"1.0","type":"link"}