Approval Details

Valid E.O.


This Executive Order approved the specified parts on on November 15, 2007.
As of Wednesday, February 28th, 2024 this Executive Order has not been overturned or superceeded.

Approved Parts

Part NumberModelsRemarks
THY-5112000 to 2004 Tacoma, 4Runner 2/4wd with 2.4 or 2.7L engineThe Summit Industries, Inc.ÔÇÖs Thorley Headers are a shorty style header that is manufactured out of 14 gage mild steel with either a chrome or ceramic finish. The oxygen sensor is retained in the stock location and at a collector. The headers may include a connecting Y-pipe that is also manufactured out of 14 gage mild steel.

This Executive Order may be listed as:
  • C.A.R.B.E.O. D-540-4
  • Executive Order 540-4 / D540-4
  • ARB # D-540-4
  • Executive Order No: D-540-4
  • C.A.R.B. No. D-540-4
  • Resolution D-540-4
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-540-4 PDF

D-540-4 Document:

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