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USD 1199
Part #: BT46521

Bully Dog 46521 Heavy Duty ECM Tuner

1995-2010 CAT C11, C12, C13, C15, C16 (See Application Guide)
Part #: BT46521
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The Bully Dog 46521 Heavy Duty ECM Tuner is the perfect product for those fleet owners who want to tune and go. This Heavy-Duty tuner is streamlined to include 3 power levels, a speed limiter calibration features, and a DTC trouble code reader. The beauty of the ECM Tuner is in its simplicity; simply select your desired power level for the drive ahead, complete the install and store the tuner on-board to enjoy the perks of Bully Dog tuning.

  • 6% - 15% Power Increase
  • Speed Limiter Adjustments 
  • 6% - 12% Fuel Mileage Increase 
  • Diagnostic Trouble Code Reader
Power Levels:
  • Economy (6%-10% Gain)
  • Economy & Power (6%-12% Gain, 35HP-75HP)
  • Power (15% Gain, 75HP-100HP)
1995-1998 14.6L CAT 3406E
1995-1998 15.8L CAT 3406E
2002-2010 7.2L CAT C-7
2004-2010 9.3L CAT C-9
1999-2003 10.3L CAT C-10
2004-2010 11.1L CAT C-11
1997-2003 12.0L CAT C-12
2004-2010 12.5L CAT C-13
1999-2003 14.6L CAT C-15
2005-2010 15.2L CAT C-15 ACERT
1999-2003 15.8L CAT C-16
1999-2003 18.1L CAT C-18


  • MFG. Number 46521
  • Manufacturer Name Bully Dog Heavy Duty
  • Shipping Weight 5.00 lb.
  • Shipping Length 11 in.
  • Shipping Width 4 in.
  • Shipping Height 14 in.
  • Fuel Type Diesel
  • UPC 681018465212
  • Prop 65 WARNING: Cancer & Reproductive Harm -


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Emissions Notice

This product is not legal for sale or street use in California. Certain aftermarket products are subject to governmental emission standards regulated by the California Air Resources Board. In order for these products to be legal on a specific vehicle in California, the part number must receive a CARB Executive Order (EO) number. This number makes the part legal for use only on specific years, makes and models of vehicles. A decal with CARB EO number for these parts must be displayed in the engine bay to satisfy smog inspection requirements.