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Information on Changing Horsepower and Torque Rating - Policy and Procedures (Isuzu Only Dealers)

Subject:Information on Changing Horsepower and Torque Rating -- Policy and Procedures (Isuzu Only Dealers)

Models:2004i*-2006 Isuzu H and F-Series Medium Duty
with 6HK1-TC Diesel Engine or 7.8L Duramax™ Diesel Engine (VIN 3 -- RPO LG4)
(*2004 Vehicles with RPO Code CTF are eligible)


This bulletin is intended to assist dealers in changing the horsepower (hp) and torque prior to or after delivery to help better fit the customer's needs. If it becomes necessary to change the hp and torque rating on a 6HK1-TC/7.8L diesel engine, please follow the listed procedure in order to determine if the unit is capable of handling the increased hp and torque.

Policy and Procedures When Changing Options

  1. Review the appropriate model year and check the compatibility chart listed in order to determine if the requested hp is available with how the vehicle is built.
  2. If the chart shows compatibility, fax the dealer request form to Partech at (248) 364-0370 to receive approval and initiate the hp upgrade process. Or call Partech at (248) 276-0213.
  3. Once approved, Partech will open a problem tracking report (PTR).
  4. PTR numbers assigned.
  5. ECM removed from vehicle and sent via overnight to Partech for recalibration.
  6. Once the ECM arrives, Partech will recalibrate the ECM.
  7. The program cost is a $100.00 administrative fee and the appropriate charges between the hp differences will be drafted from the dealer's account.
  8. After recalibration, the ECM and new hp engine label are overnighted back to the dealer.
  9. Reinstall the ECM into the vehicle.
  10. Remove the original hp/torque tag from the valve cover and adhere the new tag reflecting the change (EPA Compliance).
  11. Test drive the truck to ensure that there are no concerns.
  12. The ECM hp/torque change is complete.

Important: There are NO learning procedures required for this ECM. All option content and fuel injector flow rate information previously stored in the ECM will remain unaffected. Consult the appropriate service information for further explanation.

Important: If any concerns arise, please contact your DSM, DSPM or GMICT Technical Assistance at 1-800-MediumD (1-800-633-4863), prompt 3.