What Causes Mismatch Between Speed and Gear in Automatic Transmission?

[MaciAnn]

Transmission malfunction requires professional repair. Below are key points about automatic transmissions: 1. Operating Principle: Engine power is transmitted through the gearbox, a critical factor affecting fuel consumption. Generally, automatic transmissions consume 10%+ more fuel than manual ones. More gears mean better fuel efficiency for both types. 2. Driving Tips: For manual transmissions, upshift at higher RPMs. Engines are designed to operate optimally at higher revolutions - components' dynamic balance and rotational inertia parameters are calibrated accordingly. Prolonged low-RPM operation increases internal wear, causing vibration/detonation and reducing lifespan. Shifting at 3000RPM maintains post-shift RPM around 2300, keeping the engine within its healthy operating range.

[ElainaAnn]

In my over 20 years of driving experience, I've seen quite a few cases of automatic transmission speed-gear mismatch. Last time my old car was stuck at high RPMs without gaining speed, making an annoying buzzing sound. Turned out the transmission valve body was stuck, causing delayed shifting due to insufficient oil pressure. Sometimes overheating transmission fluid or cooling system issues can also confuse the computer controls. When this happens, I suggest not pushing it - find a reliable repair shop immediately to check transmission fluid and sensors. Otherwise prolonged driving like this will wear out the clutch, and repairs won't come cheap.

[GabrielFitz]

As an ordinary commuter driver, I often encounter issues with my automatic transmission car not performing properly. For example, when I press the accelerator, the RPM shoots up but the speed increases sluggishly, as if the gears aren't keeping up with the rhythm. This could be due to faulty sensors sending incorrect signals, or aged transmission fluid messing up the shifting logic. My friend's car had this problem before, and it improved significantly after changing the transmission fluid. Ignoring it not only increases fuel consumption but also makes the car feel unstable at highway speeds, affecting daily commuting efficiency and safety. I recommend paying attention to your car's responses and conducting regular minor inspections to prevent such issues.

[Claire]

Although I'm not a car repair expert, I understand some principles of automatic transmissions. Speed gear mismatch is usually caused by computer control system errors, such as the ECU not receiving correct vehicle speed signals, or sensor short circuits disrupting shift points. It could also be due to worn or slipping clutch components, leading to poor power transmission. In such cases, the car may shake or produce loud noises, affecting driving comfort. A simple solution is to use an OBD scanner to read fault codes or check if the transmission fluid level is normal. Maintaining good driving habits, like avoiding sudden acceleration, can help mitigate this issue.