Why 800,000 GM Transmissions are Shuddering: 8L-45 Autopsy Reveals How It Works & Why They FAIL!

The GM 8-speed "shudder" is mechanical nightmare for nearly 800,000 vehicle owners. In today’s video, I'm tearing down a complete 8L-45 8-speed automatic transmission teardown from a Cadillac CTS to find out exactly what is happening inside these units. From the valve body to the torque converter, I'll reveal the engineering flaws, factory fill fluid issues the "Chevy Shudder" causes, and why these units are failing at such high rates. The vehicle in this video is from a 2016 Cadillac CTS with 140,000km on it. Topics Covered In this Teardown: How it Works: A step-by-step breakdown of the GM 8L45 architecture and how it is related to the 8HP ZF design. The 8L-90 is a larger, heavy duty version used in the trucks and suffers from the same issues. The Failure Point: I'll cut open and inspect the Torque Converter Clutch (TCC) for the infamous glazing and heat damage that causes the "rumble strip" sensation we call shuddering. How it Works together: I'll disassemble each planetary gearset, wet AT clutch and valve body to explain how it works. Fluid Analysis: Why the original GM fluid was a disaster and how moisture (hydroscopy) led to the failure of 800,000+ units. TSB bulletin number 16-NA-019 suggests to perform a fluid flush with Mobil 1 Synthetic LV ATF HP. Internal Autopsy: I pull the pumps, clutches, and planetary gear sets to see if the shuddering has caused secondary metal contamination and dark spots throughout the system. Is Your Vehicle Affected? The GM 8-speed transmission (8L45/8L90) is found in a wide range of vehicles produced between 2015 and 2023, including: - Cadillac: CTS, ATS, CT6 - Chevrolet: Camaro, Colorado, Silverado - GMC: Canyon, Sierra Timestamps: 0:00 - GM 8 Speed Transmission Problem 1:01 - AWD Transfer Case Removal 1:11 - Removing the Pan: First Signs of Trouble? 2:11 - The Valve Body Removal 3:29 - Removing and inspecting the gears and clutches 11:22 - How a Planetary Gearset works 12:07 - Valve Body Inspection 16:02 - THE SMOKING GUN: Torque Converter Autopsy 17:46 - Why the "Shudder" Happens (The Science) 18:44 - Final Verdict: Can it be Fixed? Fluid Flushes vs. Rebuilds If you’re experiencing the GM shudder, shifting hesitations, or "hard shifts" when cold, this teardown will show you exactly what rebuilding your unit will entail. GM has won its victory appeal on the class action lawsuits regarding the "Chevy Shudder", and it is now up-to each owner to take legal action against GM for compensation on their repair. This is the Camera I use: https://amzn.to/3oaRcZX (US) https://amzn.to/3KWQ2uU (Canada) speedkar9 on Instagram and Tiktok https://www.instagram.com/speedkar9/ https://www.tiktok.com/@speedkar9 speedkar99 on Facebook and Linkedin: https://www.facebook.com/speedkar9/ https://www.linkedin.com/company/speedkar99/ Subscribe for more videos just like this: https://www.youtube.com/subscription_center?add_user=speedkar99 #transmissionteardown #chevy #lawsuit #8L45 #8L90