A/T - 1st to 2nd Gear Upshift Shudder
T-SB-0089-12
June 15, 2012
1st to 2nd Gear Upshift Shudder
Service Category
Drivetrain
Section
Automatic Transmission/Transaxle
Market
USA
Applicability
Introduction
Some 2010 - 2012 model year 4Runner vehicles equipped with the A750 transmission may exhibit a shudder condition during the 1-2 upshift. The Engine Control Module/ECM (SAE term: Powertrain Control Module/PCM) calibration and the transmission assembly have been revised to address this condition.
Production Change Information
This bulletin applies to vehicles produced BEFORE the Production Change Effective VINs shown.
Warranty Information
Parts Information
Required Tools & Equipment
Calibration Information
Repair Procedure
1. Bring the vehicle up to operating temperature and test drive the vehicle. Can a shudder or vibration be felt with light throttle ONLY during the 1-2 upshift?
^ YES - Go to step 2.
^ NO - This bulletin does NOT apply, refer to the Repair Manual for further diagnosis.
2. Does the shudder condition occur below 15mph?
^ YES - Go to step 3.
^ NO - This bulletin does NOT apply, refer to the Repair Manual for further diagnosis.
3. Replace the transmission assembly.
Refer to the Technical Information System (TIS), applicable model year 4Runner Repair Manual:
Drivetrain - Automatic Transmission/Transaxle - "A750E / A750F Automatic Transmission/Transaxle: Automatic Transmission Assembly: Removal / Installation"
^ 2010 4Runner:
^ A750E:Removal / Installation
^ A750F:Removal / Installation
^ 2011 4Runner:
^ A750E:Removal / Installation
^ A750F:Removal / Installation
^ 2012 4Runner:
^ A750E: Removal / Installation
^ A750F:Removal / Installation
4. Check for the Authorized Modifications Label affixed to the vehicle in the location shown in Figure 1. Confirm if the ECM (PCM) calibration has been updated. If the calibration ID listed is NOT the latest ECM (PCM) calibration - go to step 5.
5. Flash reprogram the ECM (PCM).
NOTE
^ The GR8 Battery Diagnostic Station MUST be used in Power Supply Mode to maintain battery voltage at 13.5 volts while flash reprogramming the vehicle.
^ For details on how to use the GR8 Battery Diagnostic Station, refer to the GR8 Instruction Manual located on the Technical Information System (TIS), Diagnostics - Battery.
Follow the procedures outlined in Service Bulletin T-SB-0064-10, "Techstream ECU Flash Reprogramming Procedure", and flash the ECM (PCM) with the NEW calibration file update.
6. Start the engine and warm it up to normal operating temperature before test driving.
7. Test drive the vehicle to confirm proper vehicle operation and ECM (PCM) initial learning. Refer to TIS, applicable model year 4Runner Repair Manual:
^ 2010 4Runner:
Drivetrain - Automatic Transmission/Transaxle - "A750E / A750F Automatic Transmission/Transaxle: Automatic Transmission System: Initialization"
^ 2011 4Runner:
Drivetrain - Automatic Transmission/Transaxle - "A750E / A750F Automatic Transmission/Transaxle: Automatic Transmission System: Initialization"
^ 2012 4Runner:
Drivetrain - Automatic Transmission/Transaxle - "A750E / A750F Automatic Transmission/Transaxle: Automatic Transmission System: Initialization"
8. Install the Authorized Modifications Label.
A. Using a permanent marker, enter the following information on the label:
^ ECM part number [Refer to the Parts Information section for the CURRENT PART NUMBER]
^ Calibration ID(s) [Refer to the Calibration Identification Chart for the NEW CALIBRATION ID]
^ Dealer Code
^ Repair Date
^ Change Authority [This Bulletin number]
B. Affix the Authorized Modifications Label to the vehicle at the location shown in Figure 1. The Authorized Modifications Label is available through the MDC, P/N 00451-00001-LBL.
9. Test drive the vehicle to confirm proper vehicle operation.
© 2012 Toyota Motor Sales, USA