Approval Details

Valid E.O.


This Executive Order approved the specified parts on on December 21, 1988.
As of Thursday, July 25th, 2024 this Executive Order has not been overturned or superceeded.

Approved Parts

Part NumberModelsModification
No. ATS 6.9L/7.3L1983-1987 model-year Ford Motor Company heavy-duty vehicles powered by a 6.9 liter Navistar International heavy-duty engine and 1988-1989 model-year Ford Motor Company heavy-duty vehicles powered by a 7.3 liter Navistar International heavy=duty diesel engineModifications to the OEM emission-related parts due to the installaion of the turbocharger include replacement of air cleaner assembly, replacement of the OEM exhaust system with a 3" diameter exhaust system, and replacement of the OEM crankcase depression regulator with parts included in the kit.

This Executive Order may be listed as:
  • C.A.R.B.E.O. D-171-4
  • Executive Order 171-4 / D171-4
  • ARB # D-171-4
  • Executive Order No: D-171-4
  • C.A.R.B. No. D-171-4
  • Resolution D-171-4
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-171-4 PDF

D-171-4 Document:

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