GM Accused Of Hiding Leaky Window Defect In Silverado And Sierra Trucks
Class Action: Leak
There is currently a proposed class action lawsuit against General Motors' Chevrolet and GMC brands. The lawsuit alleges that GM has concealed a dangerous defect in a number of 2019- to 2020-model-year Chevrolet Silverado and GMC Sierra trucks.
A leaky rear sliding window is the main focus of this lawsuit, and the suit alleges that the windows are susceptible to water intrusion, which can lead to mold growth and electrical problems.
The plaintiff, the owner of a 2019 GMC Sierra 1500, brought his truck to the dealership after experiencing water intrusion. The GMC dealership repaired his car, but he incurred over $1,000 in out-of-pocket costs that were not covered under GMC's warranty program.
Leaky Rear Window Issue
According to the 16-page lawsuit, certain Chevy Silverado and GMC Sierra models are affected by the issue, which include the 2020 Silverado 1500, 2020 Silverado 2500 HD, 2020 Silverado 3500 HD, 2019 to 2020 Sierra 1500, 2020 GMC Sierra 2500 HD, and 2020 GMC Sierra 3500 HD. The lawsuit covers all individuals who purchased, leased, and used any of the above-mentioned vehicles after January 3, 2019.
As the suit states, the rear windows of the affected vehicles are leaking. The sliding window comes in two parts, the fixed section and the sliding section, both of which are made of glass, framed in plastic, and sealed in urethane.
According to the lawsuit, the rear sliding window seal can crack or leak, allowing water to enter the cabin. This, in turn, may cause damage over time, corroding the vehicle's structure, disrupting electrical systems, or ruining the interior.
The lawsuit also claims that water intrusion can invite hazardous mold growth or even electrical failure. Manufacturers are supposed to design "robust" rear windows in order to avoid water damage, the lawsuit also added.
Was GM Hiding The Issue?
Allegedly, GM was aware of the issues surrounding the affected models. The lawsuit states that it was "obvious" that the automaker was aware of the defect. Perusing the timeline, on January 3, 2019, a technical service bulletin (TSB) was issued, titled: "Water Found in Rear Interior of Cab, Water Leak at Rear Sliding Window." Moreover, the TSB was revised 12 times to log and cover vehicles with issues. The latest revision was made on March 7, 2023.
The lawsuit also claims that GM had "superior knowledge" of the defect through its dealerships, pre-release testing data, warranty data, consumer complaints, and more, according to the source. Chevy and GMC dealers also refused to cover the defect repairs for vehicles out of warranty.
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This story was originally published June 13, 2026 at 11:30 AM.