This is additional information to the "Tires" section located in Section 5 of the owner manual.
When tires are changed from the original equipment size to those adapted to railroad track gage, the Powertrain Control Module (PCM) must be reprogrammed to correct the speedometer reading. The tire pressure and TPMS (Tire Pressure Monitoring System) will also have to be reprogrammed. Refer to Bulletin #83 located on web site www.GMUPFITTER.com.
Pickup Models C/K 2500/3500: LY6 6.0L V8 Engine and MYD 6L90 Automatic Transmission, with single rear wheels (option code RO4).SUV Models C/K 2500: LY6 6.0L V8 Engine and MYD 6L90 Automatic Transmission.
Reprogramming the PCM is done with the Techline Information System at your GM truck dealer. Your dealer has the correct calibration identified by the calibration part numbers on the following chart and any later updates after this publication.
Vehicle | New Tire Size | Axle Code | Model Year | Calibration Part Number |
|---|---|---|---|---|
SUV | 225/70R19.5 | GT4 (3.73) | 2009 | 12628514 |
Pickup -- Regular Box | 225/70R19.5 | GT5 (4.10) | 2009 | 12628589 |
Pickup -- Long Box | 225/70R19.5 | GT4 (3.73) | 2009 | 12628515 |
Pickup -- Long Box | 225/70R19.5 | GT5 (4.10) | 2009 | 12628516 |
SUV | 225/70R19.5 | GT4 (3.73) | 2010 | 12628517 |
Pickup -- Regular Box | 225/70R19.5 | GT5 (4.10) | 2010 | 12628588 |
Pickup -- Long Box | 225/70R19.5 | GT4 (3.73) | 2010 | 12628518 |
Pickup -- Long Box | 225/70R19.5 | GT5 (4.10) | 2010 | 12628519 |
Please refer to the Light Duty Series GM BODY BUILDER BOOK or visit www.GMUPFITTER.com for further general information regarding vehicle modifications. | ||||
