Transmission and Drivetrain: Technical Service Bulletins

• Customer Interest
  • A/T Oil Pan Bolt - Leaks
  • A/T - THM 440-T4 Engine Flare or Slip On Turns
  • A/T - THM 440-T4 Flare or Slips On Turns
  • A/T - TCC Engages In 2ND Gear
  • A/T - Harsh Engagement
  • A/T - Modulator Valve Buzz Noise
  • A/T - THM 440-T4 Transaxle Slips On Takeoff
  • A/T - THM 700-R4 Pump Whine or Moan
  • A/T - Delayed Upshifts When Cold or Hot
    • Overview
    • Bulletin Covers:
    • Diagnosis and Service Procedure
    • Service Manual Reference:
  • Hub Assembly Seal - Squeak/Squawk Noise
  • A/T - Chuggle at 35 to 45 MPH
  • A/T - Slip or Shudder on 1-2 Shift, Slip or No 2nd Gear
  • A/T - THM 440-T4 Loss of Drive and/or Reverse
  • A/T - Harsh 1st-2nd Gear Shift
  • A/T - Gear Whine
  • A/T - Long/Delayed 2-3 Shift Condition
  • A/T - 1-2 Shift Shudder
  • A/T - THM 440-T4 1-2 Shift Shudder
  • A/T - Harsh Engage, Double Bump or Shudder
  • A/T - Intermittent Loss of Drive
  • A/T - No 3RD Gear (New Thrust Bearing)
  • A/T - THM 200/200C Erratic Shift Patterns
  • A/T - THM 440-T4 Erratic Shifts/No Upshifts
  • A/T - 4T60 Slipping/No Reverse
  • A/T - Intermittent No Reverse or Locks In Reverse
  • Engine, A/T - Shift/Driveability Concerns/MIL ON
  • A/T - No Movement in Drive or 3rd Gear
• By Symptom
  • Abnormal wear/deterioration
    • A/T - 3T40 Center Gearbox Distress, Diagnosis Tips
    • A/T - Torque Converter Diagnosis
    • A/T - Front Bushing Wear
    • A/T - THM 200/200C Erratic Shift Patterns
  • Chattering
    • A/T - Chuggle at 35 to 45 MPH
    • A/T - Slip or Shudder on 1-2 Shift, Slip or No 2nd Gear
    • A/T - 1-2 Shift Shudder
    • A/T - THM 440-T4 1-2 Shift Shudder
    • A/T - 440T4 Converter Clutch Shudder On Apply
    • A/T - 440T4 Converter Clutch Shudder
  • Customer Interest
    • A/T Oil Pan Bolt - Leaks
    • A/T - THM 440-T4 Engine Flare or Slip On Turns
    • A/T - THM 440-T4 Flare or Slips On Turns
    • A/T - TCC Engages In 2ND Gear
    • A/T - Harsh Engagement
    • A/T - Modulator Valve Buzz Noise
    • A/T - THM 440-T4 Transaxle Slips On Takeoff
    • A/T - THM 700-R4 Pump Whine or Moan
    • A/T - Delayed Upshifts When Cold or Hot
      • Overview
      • Bulletin Covers:
      • Diagnosis and Service Procedure
      • Service Manual Reference:
    • Hub Assembly Seal - Squeak/Squawk Noise
    • A/T - Chuggle at 35 to 45 MPH
    • A/T - Slip or Shudder on 1-2 Shift, Slip or No 2nd Gear
    • A/T - THM 440-T4 Loss of Drive and/or Reverse
    • A/T - Harsh 1st-2nd Gear Shift
    • A/T - Gear Whine
    • A/T - Long/Delayed 2-3 Shift Condition
    • A/T - 1-2 Shift Shudder
    • A/T - THM 440-T4 1-2 Shift Shudder
    • A/T - Harsh Engage, Double Bump or Shudder
    • A/T - Intermittent Loss of Drive
    • A/T - No 3RD Gear (New Thrust Bearing)
    • A/T - THM 200/200C Erratic Shift Patterns
    • A/T - THM 440-T4 Erratic Shifts/No Upshifts
    • A/T - 4T60 Slipping/No Reverse
    • A/T - Intermittent No Reverse or Locks In Reverse
    • Engine, A/T - Shift/Driveability Concerns/MIL ON
    • A/T - No Movement in Drive or 3rd Gear
  • Difficult gear selection
    • A/T - Harsh Engage, Double Bump or Shudder
  • Driveability
    • Engine, A/T - Shift/Driveability Concerns/MIL ON
  • Erratic Shifting
    • A/T - Delayed Upshifts When Cold or Hot
      • Overview
      • Bulletin Covers:
      • Diagnosis and Service Procedure
      • Service Manual Reference:
    • A/T - Early Upshift/No Kickdown
    • A/T - 440T4 Harsh 3-2 Detent Downshift
    • A/T - 440T4 Converter Clutch Shudder On Apply
    • A/T - Converter Clutch Shudder
    • A/T - 440T4 Soft/Slipping 1-2 Upshift Flare
    • A/T - THM 200/200C Erratic Shift Patterns
    • A/T - THM 440-T4 Erratic Shifts/No Upshifts
    • Engine, A/T - Shift/Driveability Concerns/MIL ON
  • Hard Shifting
    • A/T - Harsh Engagement
    • A/T - THM 440-T4 Transaxle Slips On Takeoff
    • A/T - Harsh 1st-2nd Gear Shift
    • A/T - On Car Service Info For Harsh 3-2 Downshifts
      • Overview
      • Bulletin Covers:
      • IA. Very Harsh Part Throttle 3-2 Shift At 20-40 MPH --
      • IB. Harsh 3-2 and/or 4-2 Shifts
      • IC. Intermittent Harsh Part Throttle 3-2 Shift --
      • Service Parts Information:
        • Overview
        • II. Harsh 3-2 Shift **High Altitude Only**
        • Service Parts Information:
        • Service Manual Reference:
      • III. Harsh 3-2 Shift **Low Altitude* Only**
      • Service Parts Information:
      • Service Manual Reference:
        • Overview
        • IV. Harsh 3-2 Shift Maneuver At 17-20 MPH --
        • Service Parts Information:
      • V.Harsh 3-2 Coastdown Bump 3.8L or 4.5L At 15-22 MPH --
      • Service Parts Information:
        • Overview
        • VI. Harsh Upshifts - High Altitude Only
        • Service Parts Information:
    • A/T - 440T4 Harsh 3-2 Downshift
  • Incorrect gear selection
    • A/T - No Converter Clutch Apply When Unit Is Hot
    • A/T - 440T4 No 1-2 Shift After Rebuild
  • Inoperative
    • A/T - THM 440-T4 Loss of Drive and/or Reverse
    • A/T - Intermittent Loss of Drive
    • A/T - No Converter Clutch Apply When Unit Is Hot
    • A/T - 440T4 No Vehicle Movement/Any Direction
    • A/T - No Movement in Drive or 3rd Gear
  • Leaks
    • A/T Oil Pan Bolt - Leaks
  • Loose
    • A/T - 4T60 Slipping/No Reverse
  • No shift/Incorrect gear engagement
    • A/T - TCC Engages In 2ND Gear
    • A/T - No 3RD Gear (New Thrust Bearing)
    • A/T - Early Upshift/No Kickdown
    • A/T - THM Late or No Upshifts
    • A/T - 440T4/4T60 Late or No Upshift
    • A/T - 440T4 No 1-2 Shift After Rebuild
    • A/T - 125C, 440T4 No Upshift
    • A/T - 440T4 No Vehicle Movement/Any Direction
    • A/T - Slipping or No-Shift/Metal Sealing Rings
    • A/T - THM 440-T4 Erratic Shifts/No Upshifts
    • A/T - Intermittent No Reverse or Locks In Reverse
  • Noise
    • A/T - THM 440-T4 Engine Flare or Slip On Turns
    • A/T - Modulator Valve Buzz Noise
    • A/T - THM 700-R4 Pump Whine or Moan
    • Hub Assembly Seal - Squeak/Squawk Noise
    • A/T - Gear Whine
    • A/T - 440T4 Buzzing Noise
    • A/T - 440T4 Coast-Down Clunk
    • A/T - 440T4 Noises/Improper Fluid Levels After Service
    • A/T - 440T4 Converter Clutch Shudder
    • A/T - Grinding/Growling Noise in Park on Incline
  • Overheating
    • A/T - 440T4 Overheating Of Torque Converter
  • Slipping
    • A/T - THM 440-T4 Engine Flare or Slip On Turns
    • A/T - THM 440-T4 Flare or Slips On Turns
    • A/T - THM 440-T4 Transaxle Slips On Takeoff
    • A/T - Slip or Shudder on 1-2 Shift, Slip or No 2nd Gear
    • A/T - Long/Delayed 2-3 Shift Condition
    • A/T - 440T4 2-3 Bind-Up/Slips
    • A/T - 440T4 Slipping On 2-3 Shift
    • A/T - 440T4 Slips Or No Movement Forward
  • Sticking/Binding
    • A/T - 440T4 Bind-Up/Fourth Gear After Rebuild
    • A/T - 440T4 Bind-Up In All Gears
  • Vibration
    • A/T - Harsh Engage, Double Bump or Shudder
  • Warping
    • A/T - New Clutch Plates
• All Technical Service Bulletins
  • Drivetrain - Information on Driveline Clunk Noise
  • Vehicle - Engine And Sub Systems Flushing Info. (CANADA)
  • Vehicle - Engine And Sub-Systems Flushing Recommendations
  • M/T - Operating Characteristics Information
  • A/T - Fluid Oil Cooler Flow Test
  • A/T - 2-3 Upshift or 3-2 Downshift Clunk Noise
  • A/T - Slight Vehicle Movement In Park At Start Up
  • ACDelco(R) Remanufactured Transmissions - Program Update
    • Overview
    • Warranty Coverage
    • New Warranty Registration
    • Warranty Claim Submission Procedures
  • A/T & M/T - AC Delco Remanufactured Transmissions
    • Overview
    • Warranty Coverage
    • Warranty Claim Submission Procedures
  • Steering - Procedure Identifying Torque Steer
  • A/T - Updated Pan and Gasket
  • A/T Oil Pan Bolt - Leaks
  • A/T - Repair Guidelines
  • A/T - THM 440-T4 Engine Flare or Slip On Turns
  • A/T - THM 440-T4 Flare or Slips On Turns
  • A/T - Updated Filter and Seal
  • A/T - Return to Previous Filter Design
  • A/T - TCC Engages In 2ND Gear
  • A/T - Harsh Engagement
  • A/T - Modulator Valve Buzz Noise
  • A/T - THM 440-T4 Transaxle Slips On Takeoff
  • A/T - THM 700-R4 Pump Whine or Moan
  • A/T - Service Procedure Update
    • Overview
    • Equipment and Materials Needed
    • Preparation
    • Initial Flush
    • Backflush
    • Tool Cleaning
  • A/T - 3T40 Center Gearbox Distress, Diagnosis Tips
  • A/T - Torque Converter Diagnosis
  • A/T - Delayed Upshifts When Cold or Hot
    • Overview
    • Bulletin Covers:
    • Diagnosis and Service Procedure
    • Service Manual Reference:
  • Hub Assembly Seal - Squeak/Squawk Noise
  • A/T - Chuggle at 35 to 45 MPH
  • A/T - New 2nd Gear Clutch Piston Seal
  • A/T - New Clutch Plates
  • A/T - New Input Clutch & 3rd Gear Clutch Seal Installer
  • A/T - 4T60 New Input and 3rd Clutch Seals
  • A/T - 3T40/125C New Roller Clutch
  • A/T - 4T60E 3RD Clutch Plate Identifiers
  • A/T - Slip or Shudder on 1-2 Shift, Slip or No 2nd Gear
  • A/T - THM 440-T4 Loss of Drive and/or Reverse
  • A/T - Harsh 1st-2nd Gear Shift
  • A/T - Gear Whine
  • A/T - Long/Delayed 2-3 Shift Condition
  • A/T - THM 200-4R New Design Forward Clutch
  • A/T - THM 200C New Design Forward Clutch
  • A/T - 1-2 Shift Shudder
  • A/T - THM 440-T4 1-2 Shift Shudder
  • A/T - 440T4 3rd Clutch Inner Seal Change
  • A/T - 440T4 Improved Second Clutch Inner Lip Seal
  • A/T - 440T4 3rd Clutch Plate Change
  • A/T - Final Drive Ratio
  • A/T - Revised Drive Link Wear Specification
  • A/T - Harsh Engage, Double Bump or Shudder
  • A/T - Intermittent Loss of Drive
  • A/T - No 3RD Gear (New Thrust Bearing)
  • A/T - On Car Service Info For Harsh 3-2 Downshifts
    • Overview
    • Bulletin Covers:
    • IA. Very Harsh Part Throttle 3-2 Shift At 20-40 MPH --
    • IB. Harsh 3-2 and/or 4-2 Shifts
    • IC. Intermittent Harsh Part Throttle 3-2 Shift --
    • Service Parts Information:
      • Overview
      • II. Harsh 3-2 Shift **High Altitude Only**
      • Service Parts Information:
      • Service Manual Reference:
    • III. Harsh 3-2 Shift **Low Altitude* Only**
    • Service Parts Information:
    • Service Manual Reference:
      • Overview
      • IV. Harsh 3-2 Shift Maneuver At 17-20 MPH --
      • Service Parts Information:
    • V.Harsh 3-2 Coastdown Bump 3.8L or 4.5L At 15-22 MPH --
    • Service Parts Information:
      • Overview
      • VI. Harsh Upshifts - High Altitude Only
      • Service Parts Information:
  • A/T - SRTA Model Update
  • A/T - THM 440-T4 Service Replacement Program
  • A/T - THM 44-T4 Service Manual Update Information
  • A/T - Service Replacement Transaxle Update
    • Overview
    • Srta Model Replacement Chart (4T60):
    • Srta Model Replacement Chart (4T60E):
  • A/T - Service Replacement Assembly Program
  • A/T - Unit Exchange Program
    • Overview
    • 1982-1986 THM 125C Srta Model Replacement Chart
    • 1987-1988 THM 125C Srta Model Replacement Chart
    • 1982-1986 THM 700-R4 Srta Model Replacement Chart
    • 1987-1988 THM 700-R4 Srta Model Replacement Chart
  • A/T - Core Return Product Feedback Form
  • A/T - 125/125C/440-T4 Identifying Final Drive Ratios
  • A/T - THM Control Valve Assembly Cleaning/Servicing
  • A/T - 440T4 Check Ball Location #14 Illustrated
  • A/T - Supplement To ATRASIL8725
  • A/T - 440T4 Lockup Sleeve Installation
  • A/T - 440T4 New Oil Filter Assembly
  • A/T - 440T4 Intermittent Harsh 3-2 Downshift
  • A/T - 440T4 Harsh Apply/Shudder On Reverse Application
  • A/T - Converter Clutch Solenoid Fluid Source I.D.
  • A/T - 440T4 Buzzing Noise
  • A/T - 440T4 Improved Shift Feel/2nd Clutch
  • A/T - 4T60/440T4 Changes For 1988
  • A/T - 440T4 Input Sprag Replacement
  • A/T - 440T4 2-3 Bind-Up/Slips
  • A/T - 440T4 Wiring Schematics
  • A/T - Engine Vacuum Testing
  • A/T - Diagnosing Converter Lock-Up Problems
    • Overview
    • Test # 1 - Checking For 12 Volts at Terminal -A-
      • Regular Method
      • Quick Method
    • Test # 2 - Checking For 12 Volts Across Fuse
    • Test # 3 - Checking For 12 Volts Across Brake Switch
    • Test # 4 - Adjusting/Replacing the Brake Switch
    • Test # 5 - Checking Wires For Shorts and Opens
    • Test # 6 - Checking For Ground at Terminal -D-
      • Regular Method
      • Quick Method
    • Test # 7 - Grounding the -D- Wire
      • Regular Method
      • Quick Method
    • Test # 8 - Checking Cooler Line Pressure or Surge
    • Test # 9 - Checking the Solenoid
    • Test # 10 - Checking Electrical Switches on Trans.
    • Test # 11 - Checking Lockup Apply Valve
    • Test # 12 - Checking Signal Oil Circuit
    • Test # 13 - Checking the Computer
  • A/T - 440T4 No Line Pressure Rise
  • A/T - Early Upshift/No Kickdown
  • A/T - 440T4/4T60 Spacer Plate Matching
  • A/T - How To Use A Pressure Gauge
  • A/T - 440T4 Harsh 3-2 Detent Downshift
  • A/T - AXOD/E 44T4's and 125's Chain Stretch
  • A/T - 440T4 Channel Plate Gasket Blow-Out
  • A/T - 440T4 No Upshift/Wrong Gear
  • A/T - THM Late or No Upshifts
  • A/T - 440T4 Coast-Down Clunk
  • A/T - Drive Axle and Wheel Lug Nut Torque Specifications
  • A/T - 440T4/4T60 Late or No Upshift
  • A/T - 440T4 Converter Clutch Shudder On Apply
  • A/T - No Converter Clutch Apply When Unit Is Hot
  • A/T - Converter Clutch Shudder
  • A/T - Pressure Tap Locations
  • A/T - 440T4 Noises/Improper Fluid Levels After Service
  • A/T - 440T4 Slipping On 2-3 Shift
  • A/T - 440T4 No 1-2 Shift After Rebuild
  • A/T - 440T4 Bind-Up/Fourth Gear After Rebuild
  • A/T - 440T4 Overheating Of Torque Converter
  • A/T - 125C, 440T4 No Upshift
  • A/T - 440T4 Reverse Engagement In Neutral
  • A/T - 440T4 Delayed Engagement
  • A/T - 440T4 No Vehicle Movement/Any Direction
  • A/T - 440T4 Replacing Left Axle Seal
  • A/T - Slipping or No-Shift/Metal Sealing Rings
  • A/T - Front Bushing Wear
  • A/T - 440T4 Early/Late Checkball Locations
  • A/T - 440T4 Input Sprag Clutch/Updated Part
  • A/T - 440T4 No Reverse Engagement After Rebuild
  • A/T - 440T4 Valve Body Removal & Precautions
  • A/T - 440T4 Slips Or No Movement Forward
  • A/T - 440T4 3-2 Coastdown Bump
  • A/T - 440T4 Converter Regulator Valve
  • A/T - 440T4 Blowing Fuses
  • A/T - 440T4 Plastic Oil Lube Dam
  • A/T - 440T4 Bind-Up In All Gears
  • A/T - Sprag Rotation
  • A/T - 440T4 Harsh 3-2 Downshift
  • A/T - 440T4 TCC Applies With 1-2 Upshift
  • A/T - 440T4 Converter Regulator Spring Update
  • A/T - 440T4 Lock Up And Cruise Control Problems
  • A/T - Math Formulas Part I
    • Overview
    • Shift Speed and Pressure
    • Speedometer Ratios
  • A/T - Twenty Steps To Successful Repairs
  • A/T - 4T60/440T4 Model Code Information
  • A/T - Math Part II
  • A/T - 440T4 Soft/Slipping 1-2 Upshift Flare
  • A/T - 440T4 Reverse Reaction Plate/Valve Body Strap
  • A/T - 440T4 Converter Clutch Shudder
  • A/T - Choosing the Right ATF
  • A/T - New Transaxle Fluid
  • A/T - Proper Fluid Level Checking Procedure
  • A/T - Manual Update, Checking ATF Color, Odor & Level
  • A/T - Procedure If ATF is Antifreeze Contaminated
  • A/T - DEXRON III Fluid Introduction
  • A/T - 4T60/4T60E Drive Link Noise
  • A/T - THM 200-4R Wiring Diagram Update
  • A/T - Evaluating Peened Spacer Plates
  • A/T - THM 200/200C Erratic Shift Patterns
  • A/T - THM 440-T4 Erratic Shifts/No Upshifts
  • Drivetrain - Recommended Axle Lubricant
  • A/T - Revised 1-2 Band Assembly
  • A/T - 4T60 New Design Bands
  • A/T - 4T60 Slipping/No Reverse
  • A/T - 4T60/3T40 Grinding/Growling On Incline
  • A/T - Intermittent No Reverse or Locks In Reverse
  • A/T - Two Stackups for 3-4 Accumulator Piston & Spring
  • Drivetrain - Revised Front Drive Axle Replacement
  • Drivetrain - New Seal Protector for Drive Axle R&R
  • A/T - Revised End Play Specifications
  • A/T - 4T60 New Thermo Element/Setting Procedure
  • A/T - Throttle Valve Lever Return Spring Eliminated
  • A/T - New Bottom Pan & Controlled Compression Gasket
  • M/T - Hydraulic Clutch Bleeding Procedure Improvement
  • Engine, A/T - Shift/Driveability Concerns/MIL ON
  • A/T - No Movement in Drive or 3rd Gear
  • A/T - Grinding/Growling Noise in Park on Incline
  • A/T - Water Or Coolant Contamination Information
  • A/T - DEXRON(R)-VI Fluid Information