OEM Transmission Control Module for 2017-2025 Buick, Cadillac, Chevrolet, & GMC

What to Look For When Buying

• Proper Fit: Make sure the TCM is designed for your vehicle's year, make, and model.
• Warranty: A warranty provides peace of mind in case the TCM fails prematurely.
• Condition: If buying used, check for any signs of physical damage or corrosion.
• Reputation of Seller: Buy from a reputable seller with good reviews and a clear return policy.

Quality Indicators

What's Included

Typically, you'll receive just the Transmission Control Module itself. You may need to reuse existing mounting hardware.

Difficulty Level and Estimated Time

Installing a TCM can range from moderate to difficult, depending on your mechanical skills and the vehicle's design. Estimated time: 1-3 hours.

Special Tools Needed

• Basic hand tools (sockets, wrenches, screwdrivers)
• OBD-II scanner (for clearing codes)
• Multimeter (optional, for testing)

Critical Steps and Tips

1. Disconnect the Battery: Always disconnect the negative battery cable before working on electrical components.
2. Locate the TCM: The TCM is typically located under the dashboard, under a seat, or in the engine compartment. Consult your vehicle's repair manual for the exact location.
3. Disconnect Connectors: Carefully disconnect the electrical connectors from the TCM.
4. Remove the Old TCM: Unbolt or unclip the old TCM from its mounting bracket.
5. Install the New TCM: Install the new TCM in the mounting bracket and reconnect the electrical connectors.
6. Reconnect the Battery: Reconnect the negative battery cable.
7. Clear Diagnostic Trouble Codes (DTCs): Use an OBD-II scanner to clear any transmission-related DTCs.

DIY or Professional Installation?

If you're comfortable working on cars and have some experience with electrical systems, you may be able to install the TCM yourself. However, if you're not confident, it's best to have a professional mechanic do the job.

Used OEM

Used OEM TCMs offer excellent value. These are genuine factory parts that have been tested and inspected to ensure they're in good working condition. You get the reliability of an OEM part at a significantly lower price than a new aftermarket unit.

New Aftermarket

New aftermarket TCMs are brand new parts manufactured by third-party companies. They are designed to meet or exceed OE specifications. The quality can vary depending on the manufacturer.

Parts Commonly Replaced or Checked

• Transmission Fluid: Low or contaminated transmission fluid can cause shifting problems and damage the TCM.
• Transmission Filter: A clogged transmission filter can restrict fluid flow and put stress on the TCM.
• Wiring Harness: Damaged or corroded wiring can cause electrical problems that affect the TCM.
• Transmission Sensors (Speed Sensors, etc.): Faulty sensors can send incorrect information to the TCM, causing it to malfunction.

Preventing Repeat Failures

Replacing related parts can help prevent repeat TCM failures. For example, changing the transmission fluid and filter can ensure proper lubrication and prevent overheating. Addressing wiring issues can prevent electrical surges that can damage the TCM.

How Long This Part Normally Lasts

A TCM can last for the life of the vehicle, but its lifespan can vary depending on several factors. A typical lifespan is 100,000-150,000 miles or 7-10 years.

Factors That Affect Longevity

• Driving habits: Aggressive driving can put more stress on the transmission and TCM.
• Maintenance: Regular transmission fluid changes can help prolong the life of the TCM.
• Environmental conditions: Extreme temperatures and humidity can damage the TCM.
• Vehicle usage: Towing heavy loads can put extra strain on the transmission and TCM.

Budget vs. Mid-Range vs. Premium

• Used OEM: $150 - $300
• New Aftermarket: $200 - $400

Labor Cost Considerations

Labor costs for TCM installation can range from $100 to $300, depending on the mechanic's hourly rate and the complexity of the job.

Total Job Cost Estimates

• Used OEM: $250 - $600 (including labor)
• New Aftermarket: $300 - $700 (including labor)

Known Issues

Some vehicles within the 2018-2025 Buick, Cadillac, Chevrolet, and GMC range have reported issues with harsh shifting or transmission slipping that can be attributed to the TCM. Check for any Technical Service Bulletins (TSBs) related to your specific vehicle model and transmission. Common complaints include delayed engagement when shifting into drive or reverse.

How to Confirm Proper Operation

• Smooth Shifting: The transmission should shift smoothly and without hesitation.
• No Warning Lights: The Check Engine Light should be off.
• Normal Performance: The vehicle should accelerate and perform as expected.
• Scan for Codes: Use an OBD-II scanner to confirm that no transmission-related codes are present.

What to Look/Listen For

• Listen for any unusual noises from the transmission.
• Pay attention to how the transmission shifts under different driving conditions (acceleration, deceleration, uphill, downhill).
• Monitor fuel economy to ensure it's within the normal range.

Q: Will this TCM need to be programmed?
A: Some TCMs require programming to match your vehicle's specific VIN. Check with your mechanic or the seller to determine if programming is necessary.

Q: How do I know if my TCM is bad?
A: Common symptoms include erratic shifting, transmission slipping, a Check Engine Light, and being stuck in limp mode. A diagnostic scan can confirm if the TCM is the problem.

Q: Is it difficult to replace a TCM myself?
A: Replacing a TCM can be moderately difficult, depending on your mechanical skills. If you're not comfortable working on cars, it's best to have a professional mechanic do the job.

Q: What's the difference between a used OEM and a new aftermarket TCM?
A: A used OEM TCM is a genuine factory part that has been tested and inspected. A new aftermarket TCM is a brand new part manufactured by a third-party company.

Q: How long will a TCM last?
A: A TCM can last for the life of the vehicle, but its lifespan can vary depending on several factors. A typical lifespan is 100,000-150,000 miles or 7-10 years.

OEM Part Numbers:

• GM: 24044614, 24046814, 24049861, 24290348, 24292659, 24297413

Fits Years: 2017 2018 2019 2020 2021 2022 2023 2024 2025