Ford Escort transmission issue with failure to shift into overdrive and 4th gear on Ford Escort

Some Ford Escort owners report experiencing transmission issues that prevent shifting into overdrive and 4th gear. These issues may manifest as gear slippage, causing a sudden jerk when accelerating. Additionally, low transmission fluid levels are a common culprit, and checking and refilling the fluid may resolve the problem. Some owners have identified defective transmission solenoids as a barrier to proper gear shifting, while a faulty Overdrive (OD) button can also hinder the transition into 4th gear. Mechanical obstructions, such as problems with the shifting shaft or shift lever mechanism, can lead to difficulties in shifting. Furthermore, it is crucial for owners to ensure that the Powertrain Control Module (PCM) is receiving accurate input from sensors like the Throttle Position (TP) sensor, Transmission Range (TR) sensor, and Vehicle Speed Sensor (VSS) to facilitate smooth gear changes. Proper diagnosis and maintenance are essential for addressing these transmission concerns in the Ford Escort.