What Causes Transmission Shaking?
3 Answers
Reasons for transmission shaking: 1. Excessive carbon deposits: Too much carbon buildup inside the engine can absorb some oil during startup, leading to an overly lean air-fuel mixture. When the carbon deposits become saturated with gasoline, the engine starts operating normally. However, when the mixture is ignited, the gasoline absorbed by the carbon deposits is sucked into the cylinders by vacuum pressure, resulting in an overly rich mixture. This alternation between lean and rich conditions causes engine shaking. 2. Dirty throttle or air filter: A clogged air filter restricts sufficient air intake into the engine cylinders, disrupting the air-fuel ratio and causing insufficient engine power, which manifests as shaking. A dirty throttle can prevent it from closing properly, leading to an overly lean mixture at idle and resulting in insufficient engine power. 3. Spark plug issues: Over time, spark plugs can develop increased gaps or excessive carbon buildup on the electrodes, leading to poor sparking or insufficient ignition energy. This can cause misfiring, reduced power, and engine shaking. 4. Aging engine components: Worn-out engine mounts lose their ability to absorb vibrations, contributing to shaking.
When I experience transmission shaking issues, there are usually several common causes. First is engine mount damage, which allows engine vibrations to directly transfer to the transmission, especially noticeable during acceleration or when starting to move. Second is driveshaft imbalance - aged or damaged driveshafts can cause overall vibration. For automatic transmissions, torque converter failure is quite common, such as unstable oil pressure or internal impeller wear, resulting in jerky shifting sensations. Insufficient or contaminated transmission fluid is another issue - dirty fluid leads to inadequate gear lubrication and causes shaking. Additionally, electronic control unit malfunctions can cause system signal misjudgment, exacerbating vibrations. When shaking is detected, it's best to get it checked promptly as delay may damage more components and increase repair costs. Regular transmission fluid changes can effectively prevent such problems.
Transmission vibration is quite annoying, and I've noticed many cases stem from neglected routine maintenance. Worn or loose engine mounts can easily transmit vibrations throughout the chassis. For automatic transmissions, poor maintenance of the torque converter leads to fluctuating oil pressure that causes persistent shaking. Fluids are crucial – low or oxidized/contaminated transmission fluid reduces lubrication effectiveness, resulting in unsteady gear operation and vibration. Damaged drive shafts are also common, especially in vehicles frequently driven on rough roads. For prevention, I recommend changing transmission fluid every 2 years while inspecting mounts and drivetrain components to catch minor issues before major repairs. Additionally, when vibration occurs, don't force the vehicle – stop to check fluid levels as a basic safety precaution.
