Campaign - Replace Differential Ring And Pinion
Subject:Service Update for Inventory Vehicles Only - Ring and Pinion Gear Set Replacement - Expires September 30, 2007
# 07197 - (07/20/2007)
Models:
2007 Chevrolet Silverado
2007 GMC Sierra
Equipped With Four-Wheel Drive
THIS SERVICE UPDATE INVOLVES VEHICLES IN DEALER INVENTORY ONLY AND WILL EXPIRE SEPTEMBER 30, 2007.
Purpose
This bulletin provides a service procedure to replace the 4.10 ratio front and rear axle gear sets with a 3.73 ratio front and rear axle gear set, reprogram the body control module (BCM), transmission control module (TCM), and engine control module (ECM), and install a new service parts identification (SPID) label and price label on certain 4WD 2007 Chevrolet Silverado and 2007 GMC Sierra vehicles. On these vehicles, the combination of the 4.10 ratio axle gear sets and the BCM, TCM, and ECM calibrations could reduce the performance of the transmission.
Stock units at U.S. dealerships have been rebilled and dealers will receive new invoices for these vehicles. The option cost of the GT5 axle will appear in the Dealer's Open Account.
This service procedure should be completed on involved vehicles currently in dealership inventory as soon as possible but no later then September 30, 2007, at which time this bulletin will expire.
Vehicles Involved
A list of involved vehicles currently in dealer inventory is available on the "Service Update Bulletin Information" link under the "Service" tab in DealerWorld (GM US), or to the Dealer Communication (Canada), used to release this bulletin.
Important:
Dealers are to confirm vehicle eligibility prior to beginning repairs by using the GM Vehicle Inquiry System (GMVIS).
Parts Information
Parts required to complete this service update are to be obtained from General Motors Service and Parts Operations (GMSPO). Please refer to your "involved vehicles listing" before ordering parts. Normal orders should be placed on a DRO = Daily Replenishment Order. In an emergency situation, parts should be ordered on a CSO = Customer Special Order.
Service Procedure
1. Remove the 4.10 ratio front and rear axle gear sets from the vehicle. Refer to Drive Pinion and Ring Gear Replacement (8.6, 9.5/9.5LD, and 11.5 Inch Axles) and Front Drive Pinion and Gear Replacement (8.25 Inch Axles) in SI.
2. Install the 3.73 ratio front and rear axle gear sets into the vehicle. Refer to Drive Pinion and Ring Gear Replacement (8.6, 9.5/9.5LD, and 11.5 Inch Axles) and Front Drive Pinion and Gear Replacement (8.25 Inch Axles) in SI.
Important Calibration Information:
Contact the Techline Customer Support Center at 1-800-828-6860 for programming assistance to obtain correct calibration changes for 3.73 axle ratio and the 148 km/h (92 mph) speed calibration. To ensure that you are provided with the correct calibration, you must refer to field action bulletin 07197 and ask the Customer Support Center for the 148 km/h (92 mph) speed calibration. Also, provide the Customer Support Center with the vehicle identification number (VIN).
3. Reprogram the engine control module (ECM), transmission control module (TCM), and the body control module (BCM). Use the Tech 2 Pass-Thru Method for reprogramming the BCM. Follow the instructions below.
Notice:
Before reprogramming, please check the battery condition to prevent a reprogramming error of any of the modules due to battery discharge. Battery voltage must be between 12.5 and 13 volts during reprogramming. If the battery is not fully charged, use jumper cables from an additional battery. Be sure to turn off or disable any system that may put a load on the battery, such as automatic headlamps, daytime running lights, interior lights, heating, ventilation, and air conditioning (HVAC) system, radio, engine cooling fan, etc. A programming failure or control module damage may occur if the battery voltage guidelines are not observed. Only use approved Midtronics charger or jumper packs, etc. to maintain proper battery voltage during programming.
4. The ignition switch must be in the proper position. The Tech 2(R) prompts you to turn ON the ignition, with the engine OFF. DO NOT change the position of the ignition switch during the programming procedure, unless instructed to do so.
Make certain all tool connections are secure, including the following components and circuits:
^ The RS-232 communication cable port
^ The connection at the data link connector (DLC)
^ The voltage supply circuits
^ DO NOT disturb the tool harnesses while programming. If an interruption occurs during the programming procedure, programming failure or control module damage may occur.
^ DO NOT turn OFF the ignition if the programming procedure is interrupted or unsuccessful. Ensure that all control module and DLC connections are secure and the Tech 2 software is up to date.
^ Verify that there is a battery charge of 12 to 16 volts. The battery must be able to maintain a charge during programming. Use an additional jump battery if necessary. Only use approved Midtronics charger or Jumper Packs, etc. to maintain proper battery voltage during programming.
^ Refer to SI and Service Programming System (SPS) documentation for programming instructions, if required.
5. Affix the Service Parts Information (SPID) and Price Label in the appropriate locations on the vehicle. Revised SPID and Price labels will be mailed to you sometime the week of July 23, 2007.
Claim Information
For vehicles repaired under this service update, use the table.
Disclaimer