Approval Details

Valid E.O.


This Executive Order approved the specified parts on on March 27, 2008.
As of Friday, March 1st, 2024 this Executive Order has not been overturned or superceeded.

Approved Parts

Part NumberModelsModification
HES 2101984-2004 model year Caterpillar, Cummins, Detroit Diesel, and International heavy-duty diesel engines from 7.2 liters to 16.2 liters.Rubber hose from 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-634
  • Executive Order 634 / D634
  • ARB # D-634
  • Executive Order No: D-634
  • C.A.R.B. No. D-634
  • Resolution D-634
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-634 PDF

D-634 Document:

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