LEMON Manuals: Even more car manuals for everyone
Home >> Chevrolet >> 2002 >> Blazer 4D Utility, 4WD, Part Time >> Repair and Diagnosis >> External Pages >> Different car >> Section 82 (Automatic Transmission Diagnosis - ALLISON) >> Performance Tests >> Torque Converter Diagnosis >> Whine Noise

Whine Noise

WARNING: This page is about a different car, the 2002 GMC Sierra, 2002 GMC Cab & Chassis Sierra, 2002 Chevrolet Silverado, and 2002 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.
NOTE: Do not confuse this noise with pump whine noise, which is usually noticeable in Park, Neutral and all other gear ranges. Pump whine will vary with line pressure.

You may notice a torque converter whine when the vehicle is stopped and the transmission is in Drive or Reverse. This noise will increase as you increase the engine RPM. The noise will stop when the vehicle is moving or when you apply the torque converter clutch, because both halves of the converter are turning at the same speed.

Perform a stall test to make sure the noise is actually coming from the converter:

  1. Place your foot on the brake.
  2. Place the gearshift lever in the Drive position.
  3. CAUTION: You may damage the transmission if you depress the accelerator for more than 6 seconds.
  4. Depress the accelerator to approximately 1200 RPM for no more than 6 seconds. Listen for torque converter noise. A torque converter noise will increase under this load.