Filiberto Loza Gonzalez was washing his 2019 GMC Sierra 1500 when he found water inside the cab. Not a puddle tracked in on a wet boot. Water pooling in the back of the truck, arriving through the seam around the sliding rear window.
His dealer confirmed the leak and repaired it. The bill ran past $1,000, because at 57,134 miles the factory warranty had already lapsed and General Motors declined to cover the work.
What Gonzalez says he never knew, according to a proposed class action he filed in June 2026, is that GM had a name and a number for that failure long before he bought the truck. The company logged it in a technical service bulletin dated January 3, 2019, then revised that document twelve times over the next four years. It never turned any of those revisions into a recall.
That gap, between what GM knew and what it told owners, is the whole case.
Key Takeaways
- A California class action alleges the rear sliding rear window on 2019-2020 Chevrolet Silverado and GMC Sierra trucks leaks water into the cab, causing mold, corrosion, and electrical damage.
- The suit centers on GM technical service bulletin 18-NA-383, first issued January 3, 2019 and revised twelve times through March 2023, which the plaintiff cites as proof GM knew about the defect early.
- The problem is tied to trucks fitted with the power sliding rear window (option code A48), not the fixed rear glass.
- GM’s own bulletin traces the most common cause to cracks in a plastic glass guide hidden under the rear roof spoiler, not the rubber weatherstrip most owners would suspect.
- No safety recall was ever issued. GM handled the leak as a service-bulletin repair, which means out-of-warranty owners pay for it themselves.
- Named plaintiff Filiberto Loza Gonzalez paid more than $1,000 for a repair on his 2019 Sierra after the warranty expired at 57,134 miles.
What the Lawsuit Alleges
The complaint landed in the U.S. District Court for the Eastern District of California, brought by the Law Office of Robert L. Starr, with attorneys Robert L. Starr and Adam Rose representing the proposed class. It names General Motors as the defendant and Gonzalez as the lead plaintiff.
The legal theory rests on California’s consumer-protection statutes: the Consumers Legal Remedies Act, the state Business and Professions Code, plus counts for fraud and false advertising. The proposed class covers California buyers and lessees who acquired an affected truck first placed into service after the bulletin’s January 3, 2019 date. The filing seeks compensatory and punitive damages, declaratory relief, and a jury trial.
The class is limited to California, which matters. The affected trucks and the underlying bulletin span North America and dozens of export markets, so this is not a nationwide action. It rides California’s unusually strong consumer statutes, and any relief it wins would apply to that state’s owners.
The Leak Is Not the Seal You Can See
Popular coverage of the suit has described it as a “faulty window seal” problem. GM’s own paperwork tells a more specific story, and the distinction affects how an owner would even spot the source.
Bulletin 18-NA-383 carries the subject line “Water Found in Rear Interior of Cab, Water Leak at Rear Sliding Window.” Inside, GM pins the most frequent cause on the plastic upper rail glass guide, a component that sits above the glass and out of sight beneath the rear roof spoiler.
“The plastic upper rail glass guide may develop small fractures/cracking which allows water to pass through on the glass side of the urethane that attaches to the vehicle body.” Cracks can form on the left side, the right side, or both. Because the spoiler covers the area, an owner watching for a bad rubber gasket would be looking in the wrong place. The urethane bead that bonds the window to the body is a separate leak path the bulletin tells technicians to rule out, one fixed by resealing the window rather than replacing the cracked guide.
There is a second detail in the bulletin that reads differently once litigation is on the table. GM instructs dealers that if a truck came back after the standard repair with the same complaint, the fix is to replace the entire rear sliding window assembly. A first-line reseal, in other words, did not always hold.
Which Trucks Are Affected
The defect applies to Silverado and Sierra models equipped with the full-width power sliding rear window, GM option code A48. Trucks with the fixed rear glass or a manual slider are not the subject of the bulletin. Owners cross-shopping a used T1-generation truck should confirm the window option before assuming exposure.
| Model | Model years cited |
|---|---|
| Chevrolet Silverado 1500 | 2019-2020 |
| Chevrolet Silverado 2500 HD / 3500 HD | 2020 |
| GMC Sierra 1500 | 2019-2020 |
| GMC Sierra 2500 HD / 3500 HD | 2020 |
These are the fourth-generation Silverado 1500 and the redesigned Sierra 1500, both launched for 2019 on GM’s T1XX architecture. The bulletin flags the 2019 line as a new model, the first year of a fresh design, which is often when unresolved manufacturing issues surface.
A Bulletin, Not a Recall, and Why That Costs Owners
The difference between a technical service bulletin and a recall is the difference between who pays.
A recall is a safety action. The manufacturer notifies owners, and the fix is free regardless of warranty status or mileage. A service bulletin is internal guidance to dealers on how to diagnose and repair a known issue. It carries no notification requirement and no free fix. Once the warranty runs out, the repair bill belongs to the owner.
Gonzalez’s $1,000-plus invoice is the direct result of that structure. His truck was past the three-year, 36,000-mile bumper-to-bumper coverage when the leak developed, so GM billed him for a repair the company had been documenting since before his truck left the lot.
The plaintiff’s argument leans on that timeline. A bulletin revised twelve times between January 2019 and March 2023 is, in the suit’s framing, evidence of what lawyers call superior knowledge: GM understood the failure in detail, kept refining the repair, and still left owners to discover it on their own and cover the cost after warranty.
If you own a 2019-2020 Silverado or Sierra with the power sliding rear window: Check the rear footwell and the area behind the rear seat for dampness, staining, or a musty smell, especially after washing the truck or heavy rain. Water intrusion can reach floor wiring and modules, so an early catch matters. Document any dealer visit and repair invoice. File a complaint with NHTSA at nhtsa.gov if you experience the leak, which helps build the public record regulators use to decide whether an investigation is warranted.
GM Has Been Here Before
Water finding its way into a cabin is not a new problem for General Motors, and the pattern gives the current suit context.
An earlier class action targeted the 2010-2013 Cadillac SRX over sunroof drains and seals that allegedly let water into the interior, wetting carpet and fostering mold across more than 222,000 vehicles. Consumer-side attorneys have also grouped a wider set of GM models, from the Equinox and Traverse to the Acadia and Escalade, under broader water-intrusion investigations covering sunroof drains, door and window sealing, and HVAC condensation.
None of that makes the Silverado leak unique. Water-intrusion suits are a recurring genre across the industry, with parallel cases filed against Ram trucks and various European sunroof designs.
What separates this one is the paper trail.
GM created a detailed, repeatedly updated repair document. It is now the plaintiff’s central exhibit rather than the company’s defense.
What GM Has Said
As of the coverage window in June and early July 2026, GM had not issued a public statement responding to the lawsuit. Automakers routinely decline to comment on pending litigation, and the company has not addressed the specific allegations in the filing.
The nearest thing to an on-record GM position is the bulletin itself. It acknowledges the condition, identifies the cause, prescribes a repair, and escalates to a full window replacement on repeat failures. That document was written to guide dealers. In court, the plaintiff intends to read it as an admission.
Bottom Line
This case is less about a leaky window than about the line between a service bulletin and a recall, and who ends up paying when a manufacturer stays on the service-bulletin side of it. The engineering is fairly modest: a cracked plastic guide under the spoiler lets water into the cab, and GM has known the fix for years. The legal stakes are larger, because the suit asks whether four years of quiet revisions to an internal document, with no owner notification and no free repair, meets California’s bar for fraud and superior knowledge. GM will likely argue the bulletin shows responsible engineering, not concealment. Owners of 2019-2020 Silverado and Sierra trucks with the power sliding rear window have a simpler takeaway. Check the rear footwell, keep every repair receipt, and file with NHTSA if you find water where it should not be. A class action can take years to resolve. The corrosion behind your rear seat will not wait for it.
Frequently Asked Questions
What is the GM Silverado and Sierra water-leak lawsuit about?
A proposed class action filed in June 2026 in the U.S. District Court for the Eastern District of California alleges that the power sliding rear window on 2019-2020 Chevrolet Silverado and GMC Sierra trucks leaks water into the cab. The suit says GM knew about the defect, documented it in a service bulletin for four years, and never issued a recall, leaving out-of-warranty owners to pay for repairs.
Which trucks are covered by the lawsuit?
The complaint names the 2019-2020 Chevrolet Silverado 1500 and GMC Sierra 1500, plus the 2020 Silverado and Sierra 2500 HD and 3500 HD. Only trucks equipped with the full-width power sliding rear window, GM option code A48, are affected. Models with fixed rear glass or a manual sliding window are not part of the claim.
What causes the rear window to leak?
According to GM service bulletin 18-NA-383, the most common cause is cracking in a plastic upper rail glass guide located above the window, hidden beneath the rear roof spoiler. Water passes through those cracks and into the cab. The rubber-side urethane that seals the glass to the body is listed as a secondary cause. Because the spoiler covers the area, the source is hard for an owner to see.
Is there a recall for the Silverado and Sierra water leak?
No. GM addressed the condition through technical service bulletin 18-NA-383 rather than a safety recall. That distinction matters for cost: a recall repair is free regardless of mileage or warranty status, while a service-bulletin repair is only covered while the vehicle remains under warranty. Owners past warranty typically pay out of pocket.
What is a technical service bulletin, and how is it different from a recall?
A technical service bulletin is internal guidance a manufacturer sends dealers on how to diagnose and repair a known issue. It carries no owner-notification requirement and no free-repair mandate. A recall is a formal safety action that requires the manufacturer to notify owners and fix the defect at no charge. The lawsuit argues GM should have escalated the leak beyond a bulletin.
How much does the repair cost?
The named plaintiff paid more than $1,000 after his warranty expired at 57,134 miles. Actual cost varies by dealer and by whether the fix requires only resealing the glass guide or a full replacement of the rear sliding window assembly, which GM’s bulletin calls for on repeat failures.
What damage can the water leak cause?
Owners and the complaint describe water pooling in the rear interior, leading to mold growth, upholstery and carpet damage, corrosion, and electrical faults. Because water can reach floor wiring and control modules, the suit frames the leak as a potential safety concern, not only a comfort or cosmetic issue.
What should I do if my Silverado or Sierra is leaking?
Inspect the rear footwell and the area behind the rear seat for dampness, stains, or a musty odor, particularly after rain or a car wash. Take the truck to a dealer, reference bulletin 18-NA-383, and keep every diagnostic and repair invoice. File a complaint with NHTSA at nhtsa.gov, which adds to the public record regulators review when deciding whether to open an investigation.
Can I join the class action?
The proposed class currently covers California buyers and lessees of the affected trucks placed into service after January 3, 2019. The class has not yet been certified, and eligibility can change as the case proceeds. Owners who believe they qualify should follow the case through the plaintiff’s law firm or a consumer-rights attorney rather than relying on a settlement that does not yet exist.
Does this affect the resale value of a 2019-2020 Silverado or Sierra?
Only trucks with the power sliding rear window are implicated, and a truck that has already received the updated repair or window replacement carries less risk. Buyers of a used T1-generation Silverado or Sierra should check the window option, inspect the rear cab for water staining, and ask for service records showing whether the bulletin repair was performed.
Michael Kahn
Michael Kahn is the writer, photographer, and publisher behind The Weekly Driver. He cares about how cars drive and what they're like to own. He covers automobile industry news, car shows and events, and new car reviews. The reviews come from behind the wheel: day trips that favor back routes, treating a good meal as half the reason to go. He directs and produces the visual media, matching each car to a setting and mood that fit it. When he's not reviewing new cars, Michael races paddleboards, camels, and ostriches, along with the occasional exotic car on the racetrack, and has driven in every state and country visited.
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