What is the speed range for third gear in a car?

[LeJeremiah]

Third gear corresponds to a speed range of 20-40 km/h. Generally, the optimal shifting point for most cars is when the engine reaches 2000 r/min, preferably not exceeding 2500 r/min. For high-displacement or high-power engines, the maximum efficiency range may extend further, so shifting around 3000 r/min can be considered. Different vehicles have varying engine and transmission performances. Drivers can identify the shifting point by listening to the engine sound. Typically, a dull engine sound indicates it's time to upshift. Driving in a lower gear at this point increases engine pressure, fuel consumption, and negatively impacts both the engine and transmission. Additionally, downshifting should be considered when the engine speed drops below around 1500 r/min. Upshifting timing: When the engine has ample power, it produces a dull humming sound. After upshifting, if there is no power deficiency or drivetrain vibration, and the vehicle accelerates smoothly and naturally, it indicates the upshifting timing is accurate. Downshifting timing: When both vehicle speed and engine speed continuously decrease, and the car feels sluggish with noticeable engine compartment vibration, it's time to downshift one gear. Downshifting too early will cause a noticeable jerk, wasting power and increasing fuel consumption while also affecting the engine and transmission lifespan. Downshifting too late will result in continued power deficiency even after shifting down, leading to persistent jerking. Misjudging the shifting timing will cause such irreparable consequences, inevitably affecting the driving experience.