5-Piece Mercedes M157 Idler Pulley Set – Billet Upgrade E63 CLS63 S63

Give your M157 5.5L BiTurbo the belt drive it deserves. This 63 AMG 5-Piece Idler Pulley Set – Billet Upgrade for M157 V8 Bi-Turbo replaces aging factory plastic or stamped pulleys with a complete set of CNC-machined billet aluminum idlers, built to handle tuned power levels, heat, and long-term use.

The OEM idler pulleys on the M157 AMG V8 are known to wear, crack, or fail over time—especially on tuned cars. Factory units can cause belt slip, squeal, inconsistent boost, and in severe cases full belt failure 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.

🔧 Key Features – Billet Idler Pulley Set for M157

• CNC-machined billet aluminum: Replaces weak plastic or stamped pulleys with rigid, high-strength aluminum built for heat and boost.
• Hard-anodized finish: Corrosion-resistant, wear-resistant coating for long service life in harsh engine bay conditions.
• ZZ-rated Nachi high-speed bearings: Premium bearings for smooth, quiet operation and excellent longevity.
• Complete 5-piece coverage: Includes all five main idler locations to refresh the entire M157 belt path in one kit.
• Direct OEM replacement: No modifications required—bolts in place of the factory pulleys using OEM-style locations.
• Improved belt tracking: Helps maintain consistent accessory drive and stable boost on tuned or hard-driven AMGs.
• Made in the USA by ASP Performance: Manufactured to motorsport-grade standards for serious M157 builds.

📈 Performance & Reliability Benefits

• Reduces belt slip and noise caused by worn or failing factory pulleys.
• Supports consistent boost by keeping belt tension and routing stable under load.
• Protects against failure that can damage accessories or leave you stranded.
• Ideal for tuned M157 engines running higher boost, upgraded cooling, or track use.

📦 What’s Included

• (5) CNC billet aluminum idler pulleys (complete M157 set)
• Pre-installed ZZ-rated Nachi performance bearings
• OEM-spec hardware as required for installation

✔️ Compatibility – M157 5.5L BiTurbo AMG

Direct bolt-on fit for Mercedes-Benz models equipped with the M157 AMG V8 BiTurbo:

*Fitment years may vary slightly by market and facelift. If you’re unsure whether your S 63, SL 63, or SUV/coupe 63 AMG uses the M157, send us your VIN and we’ll confirm compatibility before you order.

🧰 Installation

• Direct bolt-on replacement for OEM idler pulleys.
• Typical install time: ~1–2 hours with basic hand tools.
• No tuning required.
• Compatible with OEM and most aftermarket belt configurations.

🏁 Designed, Tested & Approved for AMG Use

We’ve spent over 12 years building, tuning, and daily-driving AMG platforms—including multiple M157-powered E 63, CLS 63, and SUV 63 builds. Partnering with ASP Performance allows us to offer a pulley solution that matches the way these cars are really used: high heat, high load, and 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.