- Transmission Fluid Level: Check the transmission fluid level and condition. If the fluid is low or dirty, it can cause shifting problems.
- Shift Solenoids: The shift solenoids control the shifting of the transmission. If one or more of the solenoids are faulty, it can prevent the transmission from shifting into overdrive.
- Governor Pressure Sensor: The governor pressure sensor monitors the transmission fluid pressure and sends a signal to the transmission control module (TCM). If the sensor is faulty, it can cause the TCM to receive incorrect information, which can lead to shifting problems.
- Transmission Control Module (TCM): The TCM controls the shifting of the transmission. If the TCM is faulty, it can prevent the transmission from shifting into overdrive.
It's important to note that these are just a few of the possible causes, and there may be other factors at play. If your Buick Park Avenue is not shifting into overdrive, it is recommended to have it diagnosed by a qualified mechanic to determine the exact cause and have it repaired accordingly.
