Approval Details

Valid E.O.


This Executive Order approved the specified parts on on April 15, 2010.
As of Monday, July 22nd, 2024 this Executive Order has not been overturned or superceeded.

Approved Parts

Part NumberModelsModification
Hydro-Zilla1970-2006 model year all heavy-duty diesel engines from 5.0 liters to 16.0 liters which do not have oxygen sensors or regeneration systems.Rubber hose from the device is connected to the low pressure side of the turbo.

This Executive Order may be listed as:
  • C.A.R.B.E.O. D-673
  • Executive Order 673 / D673
  • ARB # D-673
  • Executive Order No: D-673
  • C.A.R.B. No. D-673
  • Resolution D-673
For Free CARB Executive Order Status verification, email an image of the device Executive Order label as well as the Year/Make/Model and Test Group # of the vehicle to [email protected]

Download: Executive Order D-673 PDF

D-673 Document:

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