What is the reason for high RPM but the speed not increasing?

[StellaRose]

The main reason for high RPM but the speed not increasing is automatic transmission slippage, which may also be accompanied by severe wear or even burning of clutch or brake friction plates. If the automatic transmission is slipping, do not rush to disassemble it. Instead, conduct inspection and testing to identify the true cause. First, check the fluid level of the automatic transmission hydraulic oil. If the fluid level is too low or too high, it needs to be adjusted. Then, observe whether the automatic transmission is still slipping. If it continues to slip, inspect the quality of the hydraulic oil. If the hydraulic oil appears dark brown or has a burnt smell, it indicates that the friction plates of the clutch or brake or the brake band are burnt. In this case, the automatic transmission needs to be disassembled for repair. A road test can also be performed to determine if the automatic transmission is faulty. Shift the control lever into different positions to allow the car to drive. If the engine RPM suddenly increases when the automatic transmission shifts to a certain gear, but the vehicle speed does not increase accordingly, it indicates slippage in that gear. The easier it is for the engine RPM to rise during slippage, the more severe the slippage is.

[VonVivian]

Last time I drove out, the tachometer soared over 4000 RPM, but the speed was stuck at 80 km/h and wouldn't go up no matter what - totally frustrating. Later, a friend took a look and found that the clutch in my manual transmission was nearly worn out and slipping badly. If the clutch fails, no matter how fast the engine spins, the power won't transfer to the wheels, so the car naturally can't move. Automatic transmission cars have similar issues when there's insufficient transmission fluid pressure or slippage, causing poor engagement. I recommend paying attention to how the clutch feels during normal driving - if it's too soft or not smooth, there might be a problem. Replace it early to avoid major repairs later. Also, regularly check transmission fluid levels and condition, especially before long trips. If you encounter this situation while driving, don't stomp on the gas pedal - it'll just spike fuel consumption and isn't safe either.

[DelLogan]

While driving on the highway, the RPM suddenly surged but the speed didn't increase. I experienced this in an automatic transmission car, and it gave me quite a scare. It's likely due to internal transmission slippage, possibly a failed torque converter or aged/insufficient fluid. Simply put, the car wasn't effectively utilizing the engine's power, just wasting fuel. Another possibility is loose or damaged drivetrain components. If this happens, slow down and pull over immediately—don't push through. Regular maintenance like changing transmission fluid and filters every few thousand miles saves money and hassle. Breaking down mid-journey could cost a fortune in towing and repairs. Also, pay attention to unusual noises from wheels or driveshafts to catch issues early.

[JayceFitz]

High RPM but slow speed often indicates a transmission system malfunction in the vehicle. I once experienced this with my own car, and it turned out to be clutch wear causing slippage. For automatic transmissions, gearbox slippage is common. When this occurs, don't panic—gradually reduce speed and prioritize safety. Other possible causes include fuel system issues or damaged connecting parts, but avoid attempting DIY repairs. It's best to promptly visit a professional workshop for diagnosis, such as using diagnostic equipment to check for trouble codes. Don't force the vehicle to keep running, as this can significantly increase fuel consumption and potentially lead to accidents. During daily driving, pay attention to engine sounds and stop if you notice anything unusual.