What Causes an Automatic Transmission Car to Fail to Upshift Automatically?

[JeremiahLee]

Automatic transmission cars failing to upshift automatically are mostly due to faults in the automatic transmission system. Below are detailed explanations: Transmission Faults: For example, common transmission slippage can cause the vehicle to fail to upshift automatically. Inappropriate Gear Selection: Additionally, selecting an inappropriate gear or not releasing the handbrake can also result in high engine RPM without a corresponding increase in speed. Solutions: First, check the fluid level of the transmission oil. If the level is too low or too high, adjustments should be made. Both low and high oil levels, as well as transmission oil leaks, can easily cause the oil pump to suck in air, leading to poor lubrication and inadequate operation, which in turn causes slippage. 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. In such cases, it is advisable to pull over and wait for assistance to avoid further driving, which could lead to greater damage.