1. 10-Speed Automatic Transmission Problems 

GM's 10-speed (often paired with various engines in trucks and full-size SUVs) has multiple recurring complaints and recalls:

• Excessive wear on the transmission control valve body — This leads to harsh shifting, hesitation, shuddering, vibrations, loss of pressure, or in rare cases, sudden rear-wheel lockup while driving (increasing crash risk).
• Affected models and years include:
  • 2020–2022 Chevrolet Silverado 1500 / GMC Sierra 1500 (and some HD models).
  • 2022 Chevrolet Tahoe / Suburban, GMC Yukon / Yukon XL, Cadillac Escalade / Escalade ESV.
  • Also impacts some 2020–2022 Cadillac CT4/CT5/CT6 and Chevrolet Camaro with the 10-speed.
• GM has issued several recalls and expansions (including in 2025–2026) for valve body wear, software fixes to detect the issue earlier, and "do-over" repairs on prior fixes. Some owners report the problem persists even after recall service.
• Additional complaints: Lurching, noisy shifts, and progressive damage. There are ongoing class-action lawsuits alleging defective 8L90/8L45 and 10-speed units across GM brands.

Note: The 8-speed automatic (common in some mid-size or earlier full-size models) also has complaints of shuddering, harsh 2nd-gear shifts, and torque converter clutch issues, though less recalled than the 10-speed in this range.

2. Brake System Issues

• Vacuum pump or brake assist failures — Leading to harder brake pedal feel, longer stopping distances, warning lights, or inconsistent braking. A class-action lawsuit alleges this affects certain 2018–2022 Chevrolet Equinox and GMC Terrain, plus 2016–2020 Buick Envision (vehicles not fully covered in GM's earlier 2019 brake recall).
• Brake pressure sensor/switch problems — Electrical shorts that can overheat and raise fire risk (separate recalls on some Silverado trucks and other models).
• Master brake cylinder defects alleged in lawsuits for some 2023–2025 full-size SUVs.

3. Electrical and Software Glitches

• Blank or malfunctioning instrument panel displays (no speed, warning lights, etc.).
• Issues with electronic stability control (ESC) warning systems.
• Infotainment/radio software problems, including missing owner's manual downloads in some 2025–2026 models.
• General electrical shorts or module failures reported across various models.

4. Problems such as Brake Assist

• Mid-size SUVs (Equinox, Terrain, Traverse, Acadia, Enclave/Envision): Brake assist complaints (as noted above); some new Traverse models have transmission control module (TCM) and temperature sensor failures shortly after purchase. GMC Acadia appears in lower reliability rankings for various issues.
  
  
  

  • • Legal Remedies 
      
      You may be entitled to compensation or repurchase if your car had repeated problems.  

  • Warranty of Merchantabillty Vehicles should be reasonably fit and a car with repeated problems may violate that rule. 
  • Express Warranty
  • Lemon law Multiple visits during a specified time period can allow a lemon law claim. 
    
    
  • Problems with your 2020-26 GM transmission, call (973) 598-1980 or (973) 479-5515 for a Free Consultation