STILLEN 2009-2015 Nissan Maxima / 2007-2012 Altima 3.5L Underdrive Performance Lightweight Crank Pulley - 400344

The STILLEN Underdrive Performance Lightweight Crank Pulley is engineered to reduce rotating mass and parasitic loss in Nissan’s 3.5L V6 engine, delivering improved throttle response and measurable power gains. Factory steel crank pulleys are heavy and inefficient, requiring engine power just to keep them spinning. STILLEN eliminates this performance loss with a precision-machined billet aluminum design.

Manufactured from 6061 aerospace-grade billet aluminum, this crank pulley is CNC turned, milled, and balanced using CAD-based designs to ensure strength, accuracy, and long-term reliability. 304 stainless steel sleeves are integrated at main seal contact points to prevent wear, while factory timing marks are retained and keyways are precision broached for proper alignment and installation.

This is an underdrive pulley, featuring an approximate 20% reduction in accessory drive speed. By slowing down engine accessories, the drivetrain experiences less parasitic drag, allowing additional horsepower to be transferred directly to the wheels. The result is quicker engine revving, stronger acceleration, and improved overall performance.

With weight savings of up to 80% compared to the factory pulley, and lighter than many aftermarket alternatives, STILLEN has recorded gains of up to 10+ wheel horsepower in real-world testing. This pulley reflects STILLEN’s long-standing experience in machining precision components for high-performance and supercharged applications.

Fitment:

• 2009–2015 Nissan Maxima 3.5L
• 2007–2012 Nissan Altima 3.5L
• Emissions Notice: Not for sale or use in California

Key Features:

• Underdrive performance crank pulley
• 6061 aerospace-grade billet aluminum construction
• Approximately 20% underdrive ratio
• Dramatically reduced rotating mass
• CNC machined, milled, and balanced
• 304 stainless steel seal contact sleeves
• Factory timing marks retained
• Precision-broached keyways
• Designed and manufactured by STILLEN

Installation Notes:

• Requires shorter serpentine belt
• Correct replacement belt: STILLEN part number 400344B

Performance Benefits:

• Increased wheel horsepower
• Faster engine revving and throttle response
• Reduced parasitic drag from accessories
• Improved acceleration and drivetrain efficiency

Technical Details:

• Material: 6061 billet aluminum
• Design: Underdrive crank pulley
• Approximate Underdrive: 20%
• Part Number: 400344
• Manufacturer: STILLEN