how to fix GMC Sierra T1XX (2019-Present) transmission jerking when shifting

GMC Sierra T1XX (2019-Present)

Error Codes

2-4 hours

Time

medium

Difficulty

medium

Severity

3 min read

582 words

Problem Statement

Learn how to diagnose and fix transmission jerking in GMC Sierra T1XX (2019-Present). Step-by-step guide with symptoms, diagnostic steps, and repair instructions.

Affected Component

Transmission

Estimated Time

2-4 hours

⚠️ Safety Warnings

Important safety information - read before proceeding

•Disconnect the battery before working on electrical systems.
•Allow the engine to cool before handling any components related to the transmission.

Symptoms

•Jerking or harsh shifting during acceleration or deceleration
•Delayed engagement when shifting from park to drive or reverse
•Unusual noises during shifts (clunks or thuds)
•Check engine light illuminated
•Slipping sensation during gear changes

Diagnostic Steps

1
Scan for error codes using an OBD-II scanner to identify any transmission-related trouble codes.
2
Check the transmission fluid level and condition; look for discoloration or burnt smell.
3
Inspect for any visible leaks around the transmission and associated components.
4
Test drive the vehicle and pay attention to when the jerking occurs, noting any specific patterns.
5
Update the transmission control module (TCM) software using a compatible diagnostic tool.
6
Inspect the transmission mounts for wear or damage that could contribute to jerking.

Solution

💡 Expert Tip

For complex repairs like this, consider taking photos at each step. This helps if you need to reverse a step or consult with a mechanic. Also, keep all removed parts organized - you may need to reference them during reassembly.

Verification

After completing the repair, verify that the issue has been resolved:

✓Test the affected component to ensure it functions correctly
✓Check for any error codes or warning lights
✓Monitor the vehicle for a few days to ensure the issue does not recur

Prevention Tips

To prevent this issue from occurring again:

•Follow the manufacturer's recommended maintenance schedule
•Address warning signs early before they develop into major issues
•Use quality parts and fluids recommended for your vehicle
•Keep detailed records of all repairs and maintenance

Tools & Equipment Required

•OBD-II scanner
•Transmission fluid pump
•Wrench set
•Fluid catch pan
•Jack and jack stands
•Torque wrench

Parts Required

•Transmission fluid (specific to the model)
•Transmission mounts (if required)

Related Faults

Share this solution

Comments

No comments yet

Be the first to share your thoughts

Back to Generation

Diagnostic Steps

1
Scan for error codes using an OBD-II scanner to identify any transmission-related trouble codes.
2
Check the transmission fluid level and condition; look for discoloration or burnt smell.
3
Inspect for any visible leaks around the transmission and associated components.
4
Test drive the vehicle and pay attention to when the jerking occurs, noting any specific patterns.
5
Update the transmission control module (TCM) software using a compatible diagnostic tool.
6
Inspect the transmission mounts for wear or damage that could contribute to jerking.

Solution

1. Preparation

Gather required tools and parts.
Park the vehicle on a level surface and engage the parking brake.
Disconnect the negative battery terminal to prevent electrical shorts.

2. Check and Replace Transmission Fluid

Tools Required: Transmission fluid pump, wrench set, fluid catch pan.
Steps:
1. Locate the transmission dipstick and remove it to check fluid level.
2. If the fluid is low or dirty, use a fluid pump to drain the old transmission fluid into the catch pan.
3. Replace with the manufacturer-recommended transmission fluid (check the owner’s manual for specifications).
4. Recheck the fluid level using the dipstick, ensuring it falls within the recommended range.

3. Update Transmission Control Module (TCM)

Tools Required: OBD-II scanner capable of software updates.
Steps:
1. Connect the OBD-II scanner to the vehicle’s diagnostic port.
2. Navigate to the TCM update section of the scanner.
3. Follow on-screen instructions to download and install the latest software updates for the TCM.
4. Clear any error codes from the system and disconnect the scanner.

4. Inspect and Replace Transmission Mounts (if necessary)

Tools Required: Jack and jack stands, socket set, torque wrench.
Steps:
1. Lift the vehicle using a jack and secure it with jack stands.
2. Locate the transmission mounts and visually inspect for cracks or excessive wear.
3. If damaged, use a socket set to remove the old mounts, and install new ones, tightening them to the manufacturer’s torque specifications.