Possible causes of automatic transmission howling when driving:
Problems with clutches:
* Worn or dirty friction linings, resulting in slipping or sticking when shifting.
Problems with torque converter:
* Low level of automatic transmission fluid, due to which the necessary pressure is not created for smooth gear shifting.
* Worn or damaged friction clutch or overrunning clutch, resulting in vibration and shifting noise.
Problems with planetary gear:
* Worn or damaged gear teeth, causing a metallic grinding or humming noise when shifting gears.
* Damage to the planetary gear set or bearings, which can cause loud whining and vibration.
Problems with bearings and shafts:
* Wear or damage to the bearings that provide rotation of the shafts and gears.
* Damage or imbalance of the shafts, which can cause vibration, hum or whine.
Other problems:
* Faulty automatic transmission control electronics, which does not shift gears correctly.
* Transmission fluid level is low or the wrong fluid is being used.
* Damage to the automatic transmission housing or seals, which leads to fluid leakage and a decrease in pressure.
Diagnostics and repair:
To identify the exact cause of the howling, professional automatic transmission diagnostics is required. Repairs may include replacing worn or damaged components, flushing the system, and changing the transmission fluid.