Why Shouldn't You Upshift When Overtaking?
3 Answers
Because the moment you upshift, the engine RPM immediately drops while the vehicle speed remains unchanged. Simultaneously, due to the reduced transmission ratio, the torque output from the engine to the wheels also decreases. After completing the upshift, although you can accelerate by pressing the throttle, the reduced torque output results in slower acceleration. Precautions for downshifting before overtaking: 1. Do not use downshift overtaking when the current gear has already reached its maximum speed or when the current speed exceeds the maximum speed of the lower gear. 2. If the current gear still has sufficient acceleration capability or the current speed is already adequate to overtake the target vehicle within a short time, downshift overtaking is unnecessary. 3. Although downshift overtaking can shorten the overtaking process, frequent use of this method will increase fuel consumption.
I've been driving for over 20 years, and when overtaking, you must downshift rather than upshift. This is a matter of safety and also affects efficiency. When upshifting, the engine speed drops, torque decreases, and acceleration slows down, making it easy to miss the best opportunity when overtaking, which can lead to rear-end collisions or head-on collision risks. For example, when overtaking a large truck on a national highway, the window of opportunity is very short. Downshifting allows the engine to rev high and unleash power, making the car zoom past quickly. On the contrary, upshifting will make the car accelerate sluggishly with insufficient power, especially when going uphill or fully loaded. I still remember making this mistake as a beginner and almost getting into an accident. Since then, I’ve developed the habit of checking the tachometer every time before overtaking to ensure it’s in the optimal range. Driving isn’t just about moving forward; you also need to know how to protect yourself and others. Don’t cut corners—use your brain more to go the distance.
In our repair shop, having been in contact with car owners' issues for over a decade, incorrect gear shifting during overtaking is a common problem. The reason lies in the engine characteristics: downshifting increases RPM to enter the maximum torque zone, providing strong acceleration and ample power. Upshifting, however, reduces RPM, causing the engine to operate in an inefficient zone with weaker output, making overtaking difficult and potentially leading to lugging, which can damage components. Over time, this might result in burnt clutches or piston damage. The key to safe overtaking is controlling RPM and matching gears properly. I always advise customers to downshift rather than upshift when planning to overtake—it's not a technical challenge but common sense. Good driving habits can extend a car's lifespan and reduce personal risk.
