What Causes Severe Shaking When Shifting Gears in an Automatic Transmission?
2 Answers
Severe shaking of the car body when shifting gears in an automatic transmission is due to the transmission gear oil being too viscous and dense, which makes the transmission parts more noticeably receive the power from the engine, causing the car to shake significantly. This situation requires prompt attention. Possible reasons for the transmission gear oil becoming viscous: The gear oil has been contaminated with various impurities from inside the gearbox during operation. Corresponding solutions: If contaminated with impurities, timely cleaning is sufficient. Running the air conditioning without turning off the engine consumes gasoline. When the air conditioning is on, the engine control unit increases the engine speed by about 100 RPM, which increases the engine's air intake, leading to more fuel injection and a richer air-fuel mixture. The engine computer uses this method to improve engine stability, resulting in higher gasoline consumption. Below are other impacts of running the air conditioning without turning off the engine: Increased carbon monoxide concentration: During idling, incomplete combustion of gasoline produces carbon monoxide. The longer the idling time, the higher the concentration of carbon monoxide around the vehicle. Prolonged idling while stationary can lead to extremely high carbon monoxide levels inside the car, which can cause carbon monoxide poisoning and fatalities if people are inside, leading to safety incidents. Increased carbon buildup: Idling causes incomplete combustion of gasoline, leading to carbon buildup. Severe carbon buildup can affect the normal operation of the vehicle, reducing engine displacement, increasing fuel consumption, and causing exhaust emissions to exceed standards.
When I was driving an automatic car before, I experienced gear shift shaking, which was quite annoying, and there could be many possible reasons. Dirty or insufficient transmission fluid is the most common issue, as poor oil quality can affect hydraulic pressure, leading to rough shifting and vibrations. Uneven ignition from engine spark plugs or unstable idling can also cause shaking during gear shifts—I had it fixed once and found that these parts wear out quite quickly. Additionally, problems like loose drive shafts can make the car shake as if it's an earthquake. I recommend everyone to pay attention to the fluid replacement schedule regularly. If the shaking gets severe, stop and check immediately to avoid costly transmission repairs later.
