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Ford Racing

Mustang Underdrive Pulley (2005-2010)

Product Features

  • Gain 8-10 horsepower
  • Improved fuel efficiency
  • Increased accessory (such as the alternator) life
  • 25% reduction in pulley diameter over stock
  • Fits 2005-2010 4.6 V8 Ford Mustang GTs
  • Does not fit ROUSHcharged™ vehicles
  • Part #401433

ROUSH®'s Mustang Underdrive Pulley gives your ride a bump up in horsepower, and gas mileage.

This underdrive pulley is for Mustang GT models 2005-2010 with a 4.6L engine only, and does not work with ROUSHcharged vehicles.

Gain more horsepower, gas mileage, and accessory life with the ROUSH® 25% reduction Mustang Underdrive Pulley. This pulley fits 2005-2010 Ford Mustang GTs with the 4.6L engine only, and does not work with ROUSHcharged™ vehicles.

The ROUSH Mustang Underdrive Pulley dampens damaging engine harmonic vibration, meets SFI Spec. 18.1 and has a diameter that is 25% less than stock. The benefit is that 25% less power is diverted to running accessories, such as the alternator.

As a result, more power is freed for performance. This part has been found to increase power by 8-10 hp. Due to the increased efficiency, fuel economy is also increased. In addition, because the accessories run by this belt are being run at reduced rate, their longevity is improved. 

Mustang: 2010, 2009, 2008, 2007, 2006, 2005