Slight jolts when shifting gears in an automatic transmission (AT) may be normal, especially when using low-speed gears (for example, when shifting from first to second).
Causes of mild tremors:
* Changing the torque converter: Automatic transmissions use a torque converter to transfer power from the engine to the transmission. When shifting gears, the torque converter must lock or unlock, which may cause a slight jolt.
* Shifting Planetary Gearboxes: Automatic transmissions also have planetary gears, and when changing gears, various gears and clutches must be activated, which can result in slight jolts.
* Computer adaptation: Modern automatic transmissions are controlled by a computer that adapts to the driver’s driving style. During the adaptation period, slight jolts may occur until the computer learns the optimal switching points.
Minor shocks are usually not a cause for concern if:
*They are soft and don’t feel too strong.
* The shaking is not accompanied by other symptoms such as vibration, slipping or strange noises.
* Shocks decrease or disappear after a warm-up period.
However, if the shaking is strong, sudden, or accompanied by other symptoms, this may indicate a problem with the automatic transmission and requires the attention of a mechanic:
*Low Fluid Level: Low transmission fluid levels can cause slipping and hesitating.
*Dirty Fluid: Dirty fluid can clog valves and cause shifting problems.
*Worn parts: Worn gears, clutches or torque converter can cause excessive shock.
*Electronic problems: The electronic components that control the automatic transmission can fail and cause shifting problems.