Transmission and Drivetrain: Technical Service Bulletins
- Customer Interest
- A/T Pan Bolt - Leaks
- A/T - Engine Flare or Slip On Turns
- A/T - Flare or Slips On Turns
- Engine - Stalls on Drive/Reverse Engagement
- A/T - TCC Engages In 2nd Gear
- A/T - Harsh 3-2 Downshifts, Diagnosis & Repair
- Overview
- Very Harsh Part Throttle 3-2 Shift At 20-40 MPH:
- Harsh 3-2 and/or 4-2 Shifts:
- Intermittent Harsh Part Throttle 3-2 Shift:
- Harsh 3-2 Shift **High Altitude Only**
- Harsh 3-2 Shift **Low Altitude* Only**:
- Harsh 3-2 Shift Maneuver At 17-20 MPH:
- Harsh 3-2 Coastdown Bump 3.8L or 4.5L At 15-22 MPH:
- Harsh Upshifts - High Altitude Only:
- A/T - Harsh Upshift/3-2 Shift Conditions
- A/T - Harsh Gear Engagement
- A/T - Harsh or Firm 2-3 Upshifts
- A/T - Modulator Valve Buzz Noise
- A/T - THM 440-T4 Slips or No Drive
- A/T - Intermittent Delayed Upshifts
- Hub Assembly Seal - Squeak/Squawk Noise
- A/T - Long or Delayed 2-3 Shift
- A/T - Double Bump, Harsh Engagement, Shudder P to N or R
- A/T - Delayed Neutral to Drive Engagement
- A/T - THM 440-T4 1-2 Shift Shudder
- A/T - Harsh Engagement or Engagement Shudder
- A/T - Intermittent/Complete Loss of Drive and Reverse
- A/T -THM 440-T4 Loss of Drive and/or Reverse
- A/T - Drive Link Noise in PARK/NEUTRAL Diagnosis
- A/T - Intermittent Loss of Drive
- A/T - THM 440-T4 Erratic Shifts/No Upshifts
- A/T - Harsh Engage, Bump, or Shudder, Shifting to REV
- A/T - Intermittent No Reverse or Locks In Reverse
- A/T - THM 440-T4 Harsh 1-2 Shift
- A/T - 4T60 No Reverse/Slipping or Band Distress
- A/T - No 3RD Gear, New Thrust Bearing
- Engine, A/T - Shift/Driveability Concerns/MIL ON
- A/T - No Movement in Drive or 3rd Gear
- By Symptom
- Abnormal wear/deterioration
- Chattering
- Customer Interest
- A/T Pan Bolt - Leaks
- A/T - Engine Flare or Slip On Turns
- A/T - Flare or Slips On Turns
- Engine - Stalls on Drive/Reverse Engagement
- A/T - TCC Engages In 2nd Gear
- A/T - Harsh 3-2 Downshifts, Diagnosis & Repair
- Overview
- Very Harsh Part Throttle 3-2 Shift At 20-40 MPH:
- Harsh 3-2 and/or 4-2 Shifts:
- Intermittent Harsh Part Throttle 3-2 Shift:
- Harsh 3-2 Shift **High Altitude Only**
- Harsh 3-2 Shift **Low Altitude* Only**:
- Harsh 3-2 Shift Maneuver At 17-20 MPH:
- Harsh 3-2 Coastdown Bump 3.8L or 4.5L At 15-22 MPH:
- Harsh Upshifts - High Altitude Only:
- A/T - Harsh Upshift/3-2 Shift Conditions
- A/T - Harsh Gear Engagement
- A/T - Harsh or Firm 2-3 Upshifts
- A/T - Modulator Valve Buzz Noise
- A/T - THM 440-T4 Slips or No Drive
- A/T - Intermittent Delayed Upshifts
- Hub Assembly Seal - Squeak/Squawk Noise
- A/T - Long or Delayed 2-3 Shift
- A/T - Double Bump, Harsh Engagement, Shudder P to N or R
- A/T - Delayed Neutral to Drive Engagement
- A/T - THM 440-T4 1-2 Shift Shudder
- A/T - Harsh Engagement or Engagement Shudder
- A/T - Intermittent/Complete Loss of Drive and Reverse
- A/T -THM 440-T4 Loss of Drive and/or Reverse
- A/T - Drive Link Noise in PARK/NEUTRAL Diagnosis
- A/T - Intermittent Loss of Drive
- A/T - THM 440-T4 Erratic Shifts/No Upshifts
- A/T - Harsh Engage, Bump, or Shudder, Shifting to REV
- A/T - Intermittent No Reverse or Locks In Reverse
- A/T - THM 440-T4 Harsh 1-2 Shift
- A/T - 4T60 No Reverse/Slipping or Band Distress
- A/T - No 3RD Gear, New Thrust Bearing
- Engine, A/T - Shift/Driveability Concerns/MIL ON
- A/T - No Movement in Drive or 3rd Gear
- Difficult gear selection
- Driveability
- Erratic Shifting
- A/T - Intermittent Delayed Upshifts
- A/T - Intermittent Loss of Drive
- 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 440-T4 Erratic Shifts/No Upshifts
- A/T - Intermittent No Reverse or Locks In Reverse
- Engine, A/T - Shift/Driveability Concerns/MIL ON
- Hard Shifting
- A/T - Harsh 3-2 Downshifts, Diagnosis & Repair
- Overview
- Very Harsh Part Throttle 3-2 Shift At 20-40 MPH:
- Harsh 3-2 and/or 4-2 Shifts:
- Intermittent Harsh Part Throttle 3-2 Shift:
- Harsh 3-2 Shift **High Altitude Only**
- Harsh 3-2 Shift **Low Altitude* Only**:
- Harsh 3-2 Shift Maneuver At 17-20 MPH:
- Harsh 3-2 Coastdown Bump 3.8L or 4.5L At 15-22 MPH:
- Harsh Upshifts - High Altitude Only:
- A/T - Harsh Upshift/3-2 Shift Conditions
- A/T - Harsh Gear Engagement
- A/T - Harsh or Firm 2-3 Upshifts
- A/T - Double Bump, Harsh Engagement, Shudder P to N or R
- A/T - Harsh Engagement or Engagement Shudder
- A/T - 440T4 Harsh 3-2 Downshift
- A/T - Harsh Engage, Bump, or Shudder, Shifting to REV
- A/T - THM 440-T4 Harsh 1-2 Shift
- A/T - No 3RD Gear, New Thrust Bearing
- A/T - Harsh 3-2 Downshifts, Diagnosis & Repair
- Incorrect gear selection
- Inoperative
- Leaks
- No shift/Incorrect gear engagement
- A/T - TCC Engages In 2nd Gear
- A/T - Delayed Neutral to Drive Engagement
- A/T -THM 440-T4 Loss of Drive and/or Reverse
- 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
- A/T - 4T60 No Reverse/Slipping or Band Distress
- Noise
- A/T - Engine Flare or Slip On Turns
- A/T - Modulator Valve Buzz Noise
- Hub Assembly Seal - Squeak/Squawk Noise
- A/T - Drive Link Noise in PARK/NEUTRAL Diagnosis
- 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
- Slipping
- Sticking/Binding
- 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
- A/T & M/T - AC Delco Remanufactured Transmissions
- A/T - New Bottom Pan and Controlled Compression Gasket
- A/T Pan Bolt - Leaks
- A/T - Engine Flare or Slip On Turns
- A/T - Flare or Slips On Turns
- A/T - Transaxle Oil Filter Differences
- Engine - Stalls on Drive/Reverse Engagement
- A/T - TCC Engages In 2nd Gear
- A/T - Harsh 3-2 Downshifts, Diagnosis & Repair
- Overview
- Very Harsh Part Throttle 3-2 Shift At 20-40 MPH:
- Harsh 3-2 and/or 4-2 Shifts:
- Intermittent Harsh Part Throttle 3-2 Shift:
- Harsh 3-2 Shift **High Altitude Only**
- Harsh 3-2 Shift **Low Altitude* Only**:
- Harsh 3-2 Shift Maneuver At 17-20 MPH:
- Harsh 3-2 Coastdown Bump 3.8L or 4.5L At 15-22 MPH:
- Harsh Upshifts - High Altitude Only:
- A/T - Harsh Upshift/3-2 Shift Conditions
- A/T - Harsh Gear Engagement
- A/T - Harsh or Firm 2-3 Upshifts
- A/T - Modulator Valve Buzz Noise
- A/T - THM 440-T4 Slips or No Drive
- A/T - Service Manual Procedure Update
- A/T Torque Converter - Inoperative/Failure Diagnosis
- A/T - Difficulty Removing Ignition Key/Hard Shift
- A/T - Intermittent Delayed Upshifts
- Hub Assembly Seal - Squeak/Squawk Noise
- A/T - Long or Delayed 2-3 Shift
- A/T - Inoperative Lo-Reverse Clutch Diagnosis
- A/T - Double Bump, Harsh Engagement, Shudder P to N or R
- A/T - New 2nd Clutch Piston Seal
- A/T - Revised 4TH Clutch Reaction Plates
- A/T - Delayed Neutral to Drive Engagement
- A/T - Revised Forward Clutch Piston Seals
- A/T - New Input Clutch and 3rd Clutch Seal Installers
- A/T - New Input and 3RD Clutch Inner Piston Seal
- A/T - THM 440-T4 1-2 Shift Shudder
- A/T - Harsh Engagement or Engagement Shudder
- A/T - Intermittent/Complete Loss of Drive and Reverse
- A/T -THM 440-T4 Loss of Drive and/or Reverse
- 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 - Noise Diagnosis Update
- A/T Fluid Flow Diagrams - Update
- A/T - Replacement Model Update
- A/T - Drive Link Noise in PARK/NEUTRAL Diagnosis
- A/T - Intermittent Loss of Drive
- A/T - New Input Carrier Thrust Washers
- A/T - Service Manual Update
- 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-
- 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-
- Test # 7 - Grounding the -D- Wire
- 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
- 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 - Proper Fluid Checking
- A/T - DEXRON III Fluid Introduction
- A/T - New Chain Scavenging Scoop and Sprocket Support
- A/T - THM 440-T4 Erratic Shifts/No Upshifts
- Drivetrain - Recommended Axle Lubricant
- A/T - New 1-2 and Reverse Bands
- A/T - Harsh Engage, Bump, or Shudder, Shifting to REV
- A/T - Revised Style 1-2 Band Assembly
- A/T - Intermittent No Reverse or Locks In Reverse
- A/T - THM 440-T4 Harsh 1-2 Shift
- A/T - 4T60 No Reverse/Slipping or Band Distress
- Drivetrain - New Seal Protector for Drive Axle R&R
- Drivetrain - Updated Drive Axle Removal Procedure
- A/T - Revised End Play Specification
- A/T - No 3RD Gear, New Thrust Bearing
- A/T - Updated R&R Pinion Gear Washers & Sun Gear
- 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