What is the problem with 4000 RPM at 100 km/h?

[OJace]

4000 RPM at 100 km/h indicates slight clutch slippage. Here are detailed explanations about clutch slippage: Manifestations: Clutch slippage mainly manifests as the vehicle's speed failing to increase with the engine's RPM during acceleration, resulting in the engine's power not being fully transmitted to the drive wheels, leading to weak driving performance, especially noticeable when going uphill. Causes: The main causes of clutch slippage include insufficient friction of the clutch friction plate; shifting gears too early or disengaging gears before the clutch is fully engaged; prolonged driving with the clutch partially engaged or coasting with the clutch pedal depressed; shifting or disengaging gears incompletely, and abruptly applying throttle when the gear is not fully engaged or disengaged, causing abnormal wear of the clutch plate.