Transmission and Drivetrain: Technical Service Bulletins

• Customer Interest
  • A/T - Intermittent Slip, Downshift, or Busy Cycling TCC
  • A/T - THM 440-T4 Pan Bolt Leaks
  • A/T - Harsh Engagement During Range Selection
  • A/T - 4T60 No or Slipping 3rd Gear/No Reverse/Drive
  • A/T - Shift Cable Contacts the A/C Pipe
  • Engine Controls - SES Light/Code 62 or 26, Inop TCC
  • MIL ON, Intermittent or No TCC, DTC's 62, 26 Set
  • A/T - No Second Gear
  • A/T - Slips or Shudders/Slips or No 2nd Gear Diagnosis
  • A/T - 2-3 Slip, Flare/Delayed 2-3 Upshifts
  • A/T - Intermittent Loss of Drive
  • A/T - No 3RD Gear
  • A/T - Slips In Low/Reverse or No Reverse
  • A/T - Engine Stalls When Placed Into Gear
  • M/T - Fluid Leak From Level Indicator Bore
  • M/T - High Shift, Clutch Pedal Effort
  • M/T - Neutral/Drive Gear Rattle
  • A/T - Paint Flakes In Fluid
  • A/T - 4L60 Binding/Inoperative In Reverse
  • A/T - Harsh Engagement, Double Bump or Shudder
  • A/T - 1st to 2nd Gear Shift During Cold Weather
  • A/T - 4T60 Slips in Reverse/Reverse Band Distress
  • Engine, A/T - Shift/Driveability Concerns/MIL ON
  • A/T - No Movement in Drive or 3rd Gear
• By Symptom
  • Abnormal wear/deterioration
    • A/T - Shift Cable Contacts the A/C Pipe
    • A/T - No 1st Gear/Slips In 1st Gear
    • A/T - Slips or Shudders/Slips or No 2nd Gear Diagnosis
    • A/T - Front Bushing Wear
    • M/T - High Shift, Clutch Pedal Effort
    • A/T - 4T60 Slips in Reverse/Reverse Band Distress
  • Chattering
    • A/T - 440T4 Converter Clutch Shudder
    • A/T - Harsh Engagement, Double Bump or Shudder
  • Customer Interest
    • A/T - Intermittent Slip, Downshift, or Busy Cycling TCC
    • A/T - THM 440-T4 Pan Bolt Leaks
    • A/T - Harsh Engagement During Range Selection
    • A/T - 4T60 No or Slipping 3rd Gear/No Reverse/Drive
    • A/T - Shift Cable Contacts the A/C Pipe
    • Engine Controls - SES Light/Code 62 or 26, Inop TCC
    • MIL ON, Intermittent or No TCC, DTC's 62, 26 Set
    • A/T - No Second Gear
    • A/T - Slips or Shudders/Slips or No 2nd Gear Diagnosis
    • A/T - 2-3 Slip, Flare/Delayed 2-3 Upshifts
    • A/T - Intermittent Loss of Drive
    • A/T - No 3RD Gear
    • A/T - Slips In Low/Reverse or No Reverse
    • A/T - Engine Stalls When Placed Into Gear
    • M/T - Fluid Leak From Level Indicator Bore
    • M/T - High Shift, Clutch Pedal Effort
    • M/T - Neutral/Drive Gear Rattle
    • A/T - Paint Flakes In Fluid
    • A/T - 4L60 Binding/Inoperative In Reverse
    • A/T - Harsh Engagement, Double Bump or Shudder
    • A/T - 1st to 2nd Gear Shift During Cold Weather
    • A/T - 4T60 Slips in Reverse/Reverse Band Distress
    • Engine, A/T - Shift/Driveability Concerns/MIL ON
    • A/T - No Movement in Drive or 3rd Gear
  • Driveability
    • Engine, A/T - Shift/Driveability Concerns/MIL ON
  • Erratic Shifting
    • A/T - Intermittent Slip, Downshift, or Busy Cycling TCC
    • A/T - Intermittent Delayed Upshifts When Cold or Hot
      • Overview
      • Diagnosis:
      • Service Parts Information:
    • Engine Controls - SES Light/Code 62 or 26, Inop TCC
    • A/T - Intermittent Loss of Drive
    • A/T - Early Upshift/No Kickdown
    • A/T - 440T4 Harsh 3-2 Detent Downshift
    • A/T - Converter Clutch Shudder
    • A/T - 125, 200C/200 4R, 700 R4 Hidden Residue Build Up
    • A/T - 440T4 Soft/Slipping 1-2 Upshift Flare
    • A/T - 1st to 2nd Gear Shift During Cold Weather
    • Engine, A/T - Shift/Driveability Concerns/MIL ON
  • Hard Shifting
    • A/T - Harsh Engagement During Range Selection
    • A/T - Harsh Shift Conditions Service Information
      • Overview
      • 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
      • II. Harsh 3-2 Shift **High Altitude Only**
      • III. Harsh 3-2 Shift **Low Altitude* Only**
      • IV Harsh 3-2 Shift Maneuver At 17-20 MPH
      • V. Harsh Upshifts - High Altitude Only
    • A/T - Harsh Forward Engagement
    • A/T - 125, 200C/200 4R, 700 R4 Hidden Residue Build Up
    • A/T - Harsh Engagement, Double Bump or Shudder
    • A/T - New Style 1-2 Band Assembly
  • Hard shifting/Stiff clutch
    • M/T - High Shift, Clutch Pedal Effort
  • Incorrect gear selection
    • A/T - No Converter Clutch Apply When Unit Is Hot
  • Inoperative
    • A/T - 4T60 No or Slipping 3rd Gear/No Reverse/Drive
    • MIL ON, Intermittent or No TCC, DTC's 62, 26 Set
    • A/T - Diagnosis Information LO-Reverse Clutch
    • A/T - Intermittent Loss of Drive
    • A/T - No Converter Clutch Apply When Unit Is Hot
    • A/T - No Movement in Drive or 3rd Gear
  • Leaks
    • A/T - THM 440-T4 Pan Bolt Leaks
    • A/T - Sealing of Valve Body Cover or Oil Pan
    • A/T - Shift Cable Contacts the A/C Pipe
    • M/T - Fluid Leak From Level Indicator Bore
  • Loose
    • MIL ON, Intermittent or No TCC, DTC's 62, 26 Set
    • A/T - 3T40/4T60 Noise In Park On an Incline
  • No shift/Incorrect gear engagement
    • A/T - 4T60 No or Slipping 3rd Gear/No Reverse/Drive
    • A/T - No Second Gear
    • A/T - No 3RD Gear
    • A/T - Early Upshift/No Kickdown
    • A/T - THM Late or No Upshifts
    • A/T - 440T4/4T60 Late or No Upshift
    • A/T - 125C, 440T4 No Upshift
    • A/T - Slipping or No-Shift/Metal Sealing Rings
    • A/T - No Upshift/Governor Contamination
    • A/T - 4T60 Slips in Reverse/Reverse Band Distress
  • Noise
    • A/T - 440T4 Buzzing Noise
    • A/T - 440T4 Coast-Down Clunk
    • A/T - 440T4 Converter Clutch Shudder
    • M/T - Neutral/Drive Gear Rattle
    • A/T - F-7/4T60/4T60-E - Drive Link Noise Diagnosis
    • A/T - Grinding/Growling Noise in Park on Incline
  • Slipping
    • A/T - Intermittent Slip, Downshift, or Busy Cycling TCC
    • A/T - 4T60 No or Slipping 3rd Gear/No Reverse/Drive
    • A/T - Sporadic Engagement of Torque Converter Clutch
    • A/T - Delayed Neutral to Drive Engagement
    • A/T - No 1st Gear/Slips In 1st Gear
    • A/T - 2-3 Slip, Flare/Delayed 2-3 Upshifts
    • A/T - Slips In Low/Reverse or No Reverse
    • A/T - 440T4 2-3 Bind-Up/Slips
    • A/T - 440T4 Slips Or No Movement Forward
    • A/T - 4T60 Slips in Reverse/Reverse Band Distress
  • Sticking/Binding
    • A/T - 125, 200C/200 4R, 700 R4 Hidden Residue Build Up
    • A/T - 440T4 Bind-Up In All Gears
    • A/T - 4L60 Binding/Inoperative In Reverse
  • Won't disengage
    • A/T - 4L60 Binding/Inoperative In Reverse
• 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
  • A/T - Intermittent Slip, Downshift, or Busy Cycling TCC
  • Driveaxle - Cross-Groove CV Joint Design
  • A/T - R&R of Final Drive Pinion Gear Washers & Sun Gear
  • A/T - Updated Bottom Pan with Latex Cellulose Gasket
  • A/T - THM 440-T4 Pan Bolt Leaks
  • A/T - Sealing of Valve Body Cover or Oil Pan
  • Differential Pinion Shaft Lock Screw - Service
  • A/T - New Final Drive Assembly
  • A/T - New Final Drive Assembly/Sun Gear/Output Shaft
  • A/T - Transaxle Oil Filter Differences
  • A/T - Harsh Engagement During Range Selection
  • A/T - Harsh Shift Conditions Service Information
    • Overview
    • 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
    • II. Harsh 3-2 Shift **High Altitude Only**
    • III. Harsh 3-2 Shift **Low Altitude* Only**
    • IV Harsh 3-2 Shift Maneuver At 17-20 MPH
    • V. Harsh Upshifts - High Altitude Only
  • A/T - 4T60 No or Slipping 3rd Gear/No Reverse/Drive
  • A/T - Intermittent Delayed Upshifts When Cold or Hot
    • Overview
    • Diagnosis:
    • Service Parts Information:
  • A/T - Sporadic Engagement of Torque Converter Clutch
  • A/T - Shift Cable Contacts the A/C Pipe
  • Engine Controls - SES Light/Code 62 or 26, Inop TCC
  • MIL ON, Intermittent or No TCC, DTC's 62, 26 Set
  • A/T - Delayed Neutral to Drive Engagement
  • A/T - Diagnosis Information LO-Reverse Clutch
  • A/T - 440-T4 New 2ND Clutch inner Piston Seal
  • A/T - New Input Clutch and 3rd Clutch Seal Installers
  • A/T - 4T60 New Input and 3RD Clutch Piston Seal
  • A/T - No 1st Gear/Slips In 1st Gear
  • A/T - No Second Gear
  • A/T - Slips or Shudders/Slips or No 2nd Gear Diagnosis
  • A/T - New Clutch Plates
  • A/T - THM 3T40 New Roller Clutch
  • A/T - 3RD Clutch Plate Assembly Identification
  • A/T - 2-3 Slip, Flare/Delayed 2-3 Upshifts
  • A/T - 440T4 Improved Second Clutch Inner Lip Seal
  • A/T - 440T4 3rd Clutch Plate Change
  • A/T - New THM 440-T4 Information
  • A/T - THM 440-T4 Thermal Element
  • A/T - Drive Link Wear Specifications Revised
  • A/T - Intermittent Loss of Drive
  • A/T - Updated Carrier Thrust Washers
  • A/T - No 3RD Gear
  • A/T - 3T40/4T60 Noise In Park On an Incline
  • A/T - Inspection and Repair Guidelines
  • A/T - Slips In Low/Reverse or No Reverse
  • A/T - Engine Stalls When Placed Into Gear
  • A/T - Core Return Product Feedback Form
  • A/T - Cracked Flex Plate
  • A/T - 440T4 Buzzing Noise
  • A/T - 440T4 Improved Shift Feel/2nd Clutch
  • A/T - THM 125C Sticking TCC Solenoids
  • A/T - 4T60/440T4 Changes For 1988
  • A/T - Late 1988 GM 4T60/440T4 Changes
  • A/T - 3T40, 125/125C New Spring Dowel Case Cover Pins
  • A/T - 3T40/THM 125C Intermittent or No TCC Apply
  • A/T - 440T4 Input Sprag Replacement
  • A/T - 3T40/THM 125C Forward Drum Design Changes
  • A/T - Torque Converter Identification
    • Overview
    • 298 mm Identification
    • 245 mm Identification
  • A/T - 440T4 2-3 Bind-Up/Slips
  • A/T - 440T4 Wiring Schematics
  • A/T - Engine Vacuum Testing
  • A/T - THM 125C Model Codes
  • 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 - 125C Uncontrolled Lock-Up, Kills Engine At Stop
  • 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 No Second Clutch Switch
  • A/T - 125/440 T4 Sprocket and Final Drive Identification
  • 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 - Harsh Forward Engagement
  • A/T - No Converter Clutch Apply When Unit Is Hot
  • A/T - Rapid Converter Pump Bushing Wear
  • A/T - Converter Clutch Shudder
  • A/T - 125, 200C/200 4R, 700 R4 Hidden Residue Build Up
  • A/T - Governor Pressure Switches
  • A/T - 125C, 440T4 No Upshift
  • A/T - Methods to Check for Restricted Exhaust
  • A/T - Slipping or No-Shift/Metal Sealing Rings
  • A/T - Front Bushing Wear
  • A/T - 440T4 Slips Or No Movement Forward
  • A/T - No Upshift/Governor Contamination
  • A/T - 440T4 Converter Regulator Valve
  • A/T - 440T4 Blowing Fuses
  • A/T - 440T4 Plastic Oil Lube Dam
  • A/T - THM Steel Clutch Piston Inspection
  • A/T - 440T4 Bind-Up In All Gears
  • A/T - Sprag Rotation
  • A/T - THM 125C Model Code Information
  • A/T - 440T4 TCC Applies With 1-2 Upshift
  • A/T - Checking Pressure Switches For Leaks
  • 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 - 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 - 440T4/4T60 Model Code Information
  • M/T - Fluid Leak From Level Indicator Bore
  • M/T - High Shift, Clutch Pedal Effort
  • M/T - Neutral/Drive Gear Rattle
  • M/T - Exchange Program Diagnostic Information
    • Overview
    • 1987 and 1988 Hm-282 Diagnostic Chart
      • Overview
      • Shifting:
      • Excessive Clutch Pedal Effort:
      • Hard Shifting
      • Locked-In Gear
      • Gear Clash/ Grinds
      • Noise
      • Leaks
  • A/T - Updated ATF Fluid Color/Level Check Information
  • A/T - Paint Flakes In Fluid
  • A/T - Proper Fluid Level Checking Procedure
  • A/T - DEXRON III Fluid Introduction
  • A/T - F-7/4T60/4T60-E - Drive Link Noise Diagnosis
  • A/T - 4L60 Binding/Inoperative In Reverse
  • A/T - New Thermo Element
  • A/T - 440-T4 Valve Body Clamping Plate Eliminated
  • A/T - Evaluating Peened Spacer Plates
  • A/T - New 1-2 and Reverse Band Assemblies
  • A/T - Harsh Engagement, Double Bump or Shudder
  • A/T - New Style 1-2 Band Assembly
  • A/T - 1st to 2nd Gear Shift During Cold Weather
  • A/T - 4T60 Slips in Reverse/Reverse Band Distress
  • A/T - 3T40 New Side Cover and Bottom Pan Gasket
  • Drivetrain - Revised Front Drive Axle Replacement
  • Drivetrain - New Seal Protector for Drive Axle R&R
  • A/T - Revised End Play Specification
  • 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