7 Causes of Automatic Transmission Jerking and How to Fix Them

Experiencing jerking or shuddering in an automatic transmission vehicle can be unsettling and may indicate underlying issues that need attention. 

Understanding the causes of these problems and knowing how to address them can help maintain the smooth operation of the vehicle. Here are seven common causes of automatic transmission jerking and the steps to fix them.

1. Low Transmission Fluid

Cause

One of the most common causes of jerking in automatic transmission vehicles is low transmission fluid. Transmission fluid lubricates and cools the moving parts within the transmission, ensuring smooth gear shifts.

Solution

Regularly check the transmission fluid level and top it up if necessary. Use the type of transmission fluid specified in the vehicle’s owner manual. If the fluid level is frequently low, inspect the system for leaks and repair them promptly.

2. Dirty or Contaminated Transmission Fluid

Cause

Over time, transmission fluid can become dirty or contaminated with debris and metal particles, leading to poor performance and jerking movements during gear shifts.

Solution

Change the transmission fluid and replace the filter at the recommended intervals. Flushing the transmission system can also help remove contaminants and improve performance.

3. Worn Out Transmission Components

Cause

Transmission components such as clutches, bands, and gears can wear out over time, causing the transmission to jerk during gear changes.

Solution

A thorough inspection by a professional mechanic can identify worn components. Replacing or repairing these parts is essential to restore smooth operation. Regular maintenance can help prolong the lifespan of transmission components.

4. Faulty Transmission Control Module (TCM)

Cause

The Transmission Control Module (TCM) manages gear shifts in an automatic transmission. A faulty or malfunctioning TCM can cause erratic shifting and jerking.

Solution

Have the TCM diagnosed by a professional. If the TCM is found to be faulty, it may need to be reprogrammed or replaced. Updating the software in the TCM can also resolve some issues.

5. Sensor Issues

Cause

Automatic transmissions rely on various sensors to provide information to the TCM. Faulty sensors, such as the throttle position sensor or the vehicle speed sensor, can cause incorrect shifting patterns and jerking.

Solution

Diagnose and replace any faulty sensors. Ensuring all sensors are functioning correctly can improve transmission performance and eliminate jerking.

6. Engine Performance Problems

Cause

Engine performance issues, such as misfires, vacuum leaks, or fuel system problems, can affect the transmission's operation and cause jerking.

Solution

Conduct a comprehensive engine diagnostic to identify and fix any underlying engine problems. Addressing engine issues can improve overall vehicle performance, including the transmission.

7. Transmission Software Issues

Cause

Modern automatic transmissions are controlled by software. Glitches or outdated software can lead to improper shifting and jerking.

Solution

Check for software updates from the vehicle manufacturer. Updating the transmission software can resolve many shifting issues and improve transmission behavior.

Conclusion

Automatic transmission jerking can stem from various causes, ranging from low fluid levels to software issues. Regular maintenance and prompt attention to transmission problems are crucial for keeping a vehicle running smoothly. By understanding these common causes and their solutions, it's possible to address jerking issues effectively and ensure a reliable driving experience.