{"product_id":"4-piece-mercedes-m157-idler-pulley-set-billet-upgrade-e63-cls63-s63","title":"4-Piece Mercedes M157 Idler Pulley Set – Billet Upgrade E63 CLS63 S63","description":"\u003cdiv style=\"font-family: Arial, sans-serif; max-width: 900px; margin: auto; line-height: 1.65; color: #222; font-size: 16px;\"\u003e\n\u003c!-- Lead --\u003e\n\u003cp\u003eGive your \u003cstrong\u003eM157 5.5L BiTurbo\u003c\/strong\u003e the belt drive it deserves. This \u003cstrong\u003e4-Piece Billet Idler Pulley Set\u003c\/strong\u003e replaces aging factory plastic or stamped idlers with \u003cstrong\u003eCNC-machined billet aluminum\u003c\/strong\u003e pulleys, built to handle tuned power levels, heat, and long-term use.\u003c\/p\u003e\n\u003c!-- Why It Matters --\u003e\n\u003cp style=\"margin-top: 10px;\"\u003eThe OEM idler pulleys on the \u003cstrong\u003eM157 AMG V8\u003c\/strong\u003e are known to wear, crack, or fail over time—especially on tuned cars. Factory units can cause \u003cstrong\u003ebelt slip, squeal, inconsistent boost, and in severe cases full belt failure\u003c\/strong\u003e that can take out accessories or leave you stranded. This billet set solves that problem with stronger materials, better bearings, and smoother rotation designed for real AMG use.\u003c\/p\u003e\n\u003c!-- Key Features --\u003e\n\u003ch2 style=\"margin-top: 22px; font-size: 20px;\"\u003e🔧 Key Features\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eCNC-machined billet aluminum:\u003c\/strong\u003e Replaces weak plastic or stamped pulleys with rigid, high-strength aluminum built for heat and boost.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eHard-anodized finish:\u003c\/strong\u003e Corrosion-resistant, wear-resistant coating for long service life in harsh engine bay conditions.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eZZ-rated Nachi high-speed bearings:\u003c\/strong\u003e Premium bearings for smooth, quiet operation and excellent longevity.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eDirect OEM-style replacement:\u003c\/strong\u003e No modifications required—bolts in place of the factory pulleys using OEM-style locations.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eImproved belt tracking:\u003c\/strong\u003e Helps maintain consistent accessory drive and stable boost on tuned or hard-driven AMGs.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMade in the USA:\u003c\/strong\u003e Manufactured to motorsport-grade standards for serious M157 builds.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c!-- Performance \u0026 Reliability Benefits --\u003e\n\u003ch2 style=\"margin-top: 22px; font-size: 20px;\"\u003e📈 Performance \u0026amp; Reliability Benefits\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eReduces belt slip and noise\u003c\/strong\u003e caused by worn or failing factory pulleys.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSupports consistent boost\u003c\/strong\u003e by keeping belt tension and routing stable under load.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eProtects against failure\u003c\/strong\u003e that can damage accessories or leave you stranded.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eIdeal for tuned M157 engines\u003c\/strong\u003e running higher boost, upgraded cooling, or track use.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c!-- What's Included --\u003e\n\u003ch2 style=\"margin-top: 22px; font-size: 20px;\"\u003e📦 What’s Included\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e(4) CNC billet aluminum idler pulleys\u003c\/li\u003e\n\u003cli\u003ePre-installed ZZ-rated Nachi performance bearings\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c!-- 4-piece vs 5-piece --\u003e\n\u003cdiv style=\"margin-top: 20px; padding: 14px 16px; border-radius: 8px; border: 1px solid #e0e0e0; background: #fafafa;\"\u003e\n\u003cp style=\"margin: 0 0 8px;\"\u003e\u003cstrong\u003eFour-pulley or five-pulley set?\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp style=\"margin: 0 0 8px;\"\u003eWe offer this billet idler set in two configurations. This listing is the \u003cstrong\u003efour-pulley set\u003c\/strong\u003e. The \u003ca style=\"color: #000; font-weight: bold;\" href=\"\/products\/63-amg-5-piece-idler-pulley-set-billet-upgrade-for-m157-engines\"\u003e5-Piece M157 Idler Pulley Set\u003c\/a\u003e is also available.\u003c\/p\u003e\n\u003cp style=\"margin: 0;\"\u003eNot sure which one your car takes? Send us your \u003cstrong\u003eVIN\u003c\/strong\u003e and we’ll confirm before you order.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c!-- Compatibility Table --\u003e\n\u003ch2 style=\"margin-top: 24px; font-size: 20px;\"\u003e✔️ Confirmed Fitment\u003c\/h2\u003e\n\u003cp\u003eDirect bolt-on fit for Mercedes-Benz models equipped with the \u003cstrong\u003eM157 AMG V8 BiTurbo\u003c\/strong\u003e:\u003c\/p\u003e\n\u003ctable style=\"width: 100%; border-collapse: collapse; margin: 10px 0 14px; font-size: 15px;\"\u003e\n\u003cthead\u003e\n\u003ctr style=\"background-color: #f2f2f2;\"\u003e\n\u003cth style=\"border: 1px solid #ddd; padding: 8px; text-align: left;\"\u003eChassis\u003c\/th\u003e\n\u003cth style=\"border: 1px solid #ddd; padding: 8px; text-align: left;\"\u003eModel\u003c\/th\u003e\n\u003cth style=\"border: 1px solid #ddd; padding: 8px; text-align: left;\"\u003eYears (Approx.)\u003c\/th\u003e\n\u003c\/tr\u003e\n\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd style=\"border: 1px solid #ddd; padding: 8px;\"\u003eW212\u003c\/td\u003e\n\u003ctd style=\"border: 1px solid #ddd; padding: 8px;\"\u003eE 63 AMG \/ E 63 S AMG\u003c\/td\u003e\n\u003ctd style=\"border: 1px solid #ddd; padding: 8px;\"\u003e2012–2016\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"border: 1px solid #ddd; padding: 8px;\"\u003eW218 \/ C218\u003c\/td\u003e\n\u003ctd style=\"border: 1px solid #ddd; padding: 8px;\"\u003eCLS 63 AMG \/ CLS 63 S AMG\u003c\/td\u003e\n\u003ctd style=\"border: 1px solid #ddd; padding: 8px;\"\u003e2012–2018\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd style=\"border: 1px solid #ddd; padding: 8px;\"\u003eW221\u003c\/td\u003e\n\u003ctd style=\"border: 1px solid #ddd; padding: 8px;\"\u003eS 63 AMG (M157-equipped)\u003c\/td\u003e\n\u003ctd style=\"border: 1px solid #ddd; padding: 8px;\"\u003e2011–2013\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003cp style=\"font-size: 14px; color: #444; margin: 0 0 12px;\"\u003e\u003cstrong\u003eOther M157 models — ask before ordering.\u003c\/strong\u003e If you have a \u003cstrong\u003eW222 S 63\u003c\/strong\u003e, \u003cstrong\u003eC216 CL 63\u003c\/strong\u003e, \u003cstrong\u003eR231 SL 63\u003c\/strong\u003e, \u003cstrong\u003eW166 ML 63 \/ GLE 63\u003c\/strong\u003e, \u003cstrong\u003eX166 GL 63 \/ GLS 63\u003c\/strong\u003e, or \u003cstrong\u003eW463 G 63\u003c\/strong\u003e, send us your \u003cstrong\u003eVIN\u003c\/strong\u003e and we’ll confirm the correct set for your car before you order.\u003c\/p\u003e\n\u003c!-- Recommended Mods --\u003e\n\u003cdiv style=\"margin-top: 20px; padding: 14px 16px; border-radius: 8px; border: 1px solid #eee; background: #f7f7f7;\"\u003e\n\u003cp style=\"margin: 0 0 8px;\"\u003e\u003cstrong\u003eRecommended supporting upgrades for M157 builds:\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul style=\"margin: 0 0 4px 18px;\"\u003e\n\u003cli\u003e\u003ca style=\"color: #000; font-weight: bold; text-decoration: none;\" href=\"\/products\/amg-m157-5-5l-biturbo-intake-spacer-kit-e63-cls63-s63-cl63-sl63\"\u003eM157 AMG Intake Filter Spacer Kit\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca style=\"color: #000; font-weight: bold; text-decoration: none;\" href=\"\/products\/custom-ecu-tuning-for-mercedes-e63-cls63-s63-amg\"\u003eCustom ECU Tuning for M157 5.5L BiTurbo\u003c\/a\u003e\u003c\/li\u003e\n\u003cli\u003e\u003ca style=\"color: #000; font-weight: bold; text-decoration: none;\" href=\"\/products\/m157-amg-turbo-blankets-heat-shield-upgrade-for-63-series\"\u003eM157 Turbo Blankets \u0026amp; Heat Shield Upgrade\u003c\/a\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\u003c!-- Installation --\u003e\n\u003ch2 style=\"margin-top: 22px; font-size: 20px;\"\u003e🧰 Installation\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003eDirect bolt-on replacement for OEM idler pulleys.\u003c\/li\u003e\n\u003cli\u003eTypical install time: ~1–2 hours with basic hand tools.\u003c\/li\u003e\n\u003cli\u003eNo tuning required.\u003c\/li\u003e\n\u003cli\u003eCompatible with OEM and most aftermarket belt configurations.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c!-- Trust Section --\u003e\n\u003ch2 style=\"margin-top: 26px; font-size: 20px;\"\u003e🏁 Built for How These Cars Actually Get Driven\u003c\/h2\u003e\n\u003cp style=\"margin-top: 0;\"\u003eWe’ve spent over \u003cstrong\u003e12 years\u003c\/strong\u003e building, tuning, and daily-driving AMG platforms—including multiple M157-powered E 63, CLS 63, and SUV 63 builds. High heat, high load, high expectations. If you’re serious about long-term reliability and clean power delivery, billet idlers are one of the smartest upgrades you can make to an M157.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BenzUnited Parts","offers":[{"title":"Default Title","offer_id":46556863856815,"sku":"BU-M157-IDL-SET4","price":450.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0631\/8718\/9935\/files\/4-piece-idler-pulley-set-m157-billet-upgrade.png?v=1785116071","url":"https:\/\/benzunitedparts.com\/products\/4-piece-mercedes-m157-idler-pulley-set-billet-upgrade-e63-cls63-s63","provider":"BenzUnited Parts","version":"1.0","type":"link"}