Section 255 (Automatic Transaxle - 4T40-E/4T45-E (Troubleshooting)): Troubleshooting: Noise
WARNING: This page is about a different car, the 2004 Pontiac Sunfire and 2004 Chevrolet Cavalier. However, it is still accessible from the selected car via links, so may be relevant.
RPM Sensitive Whine
| Checks | Action |
|---|---|
| DEFINITION: In All Ranges: a whine which may be sensitive to RPM load, or which ceases when the TCC engages | |
| Torque Converter (55) | Verify that the noise is internal to the torque converter by placing your left foot on the brake with the gear or selector in Drive. Momentarily stall the engine. Torque Converter noise increases under load. |
High Pitch Whine
| Checks | Action |
|---|---|
| DEFINITION: A high pitch whine which will intensify with engine RPM or which is sensitive to the oil pressure | |
| Oil Pump System | Verify that the noise is internal to the oil pump during a preliminary oil pressure check. An increase in line pressure will vary an oil pump noise. |
Popping
| Checks | Action |
|---|---|
| DEFINITION: A Popping noise, similar to popcorn popping | |
| Oil Pump System |
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Buzz or High Frequency Rattle
| Checks | Action |
|---|---|
| DEFINITION: A Buzz or High Frequency Rattle | |
|
Verify a pressure buzz by watching for a needle vibration of the pressure gage. A road test may be necessary. Refer to Road Test Procedure . |
Whine or Growl
| Checks | Action |
|---|---|
| DEFINITION: A Whine or Growl that increases and fades with vehicle speed and is most noticeable under light acceleration | |
| Drive Link Assembly System | Verify that the noise comes from the sprockets or the from the drive ink assembly, chain, by placing your left foot on the brake and by moving the gear selector from Park or Reverse. If the noise stops, check the following items. |
| Drive Chain (36) | Stretched |
| Drive Sprocket (37) and Driven Sprocket (91) |
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| Drive Sprocket Support (43) and Driven Sprocket Support (95) | The bearing outer race support is rough or nicked |
Final Drive Hum
| Checks | Action |
|---|---|
| DEFINITION: A Final Drive Noise or Hum is most noticeable under light throttle acceleration or turns | |
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Forward Ranges
| Checks | Action |
|---|---|
| DEFINITION: Noise in 1st, 2nd, 3rd, or 4th | |
|
Worn or damaged gears |
Random Ranges
| Checks | Action |
|---|---|
| DEFINITION: Noise only in certain gear ranges | |
| Refer to Range Reference . Determine the power flow and the applicable components that may be causing this noise. | |