General Motors V8 Engine Lawsuit | Defect, Recall, Settlement

General Motors faces two separate and distinct V8 engine lawsuits. The first, Siqueiros v. General Motors LLC, targeted the Generation IV 5.3L V8 LC9 engine for defective piston rings causing excessive oil consumption and engine failure across 2011–2014 trucks and SUVs. That case reached a $175 million settlement approved in October 2025, with payments beginning in December 2025 for eligible owners in California, Idaho, and North Carolina.

The second and active lawsuit targets the 6.2-liter L87 V8 EcoTec3 engine in 2019–2024 full-size trucks and SUVs. Multiple individual class actions were consolidated in late 2025 into a single federal proceeding, now styled as Rittereiser et al. v. General Motors LLC in the U.S. District Court for the Eastern District of Michigan. As of May 2026, the L87 case is in early litigation following the filing of a 389-page consolidated complaint in February 2026, with NHTSA simultaneously investigating whether GM’s April 2025 recall adequately remedied the defect.

Case 1: The 5.3L LC9 V8 Lawsuit — Siqueiros v. General Motors

The older of the two lawsuits centers on GM’s Generation IV 5.3L V8 LC9 engine, also known as the Vortec 5300. This engine was installed across a wide range of GM trucks and SUVs from 2011 through 2014, including the Chevrolet Silverado, Avalanche, Tahoe, and Suburban, and the GMC Sierra, Yukon, and Yukon XL.

The Defect: Faulty Piston Rings and Excessive Oil Consumption

Plaintiffs alleged that the LC9 engine contained defective piston rings prone to premature failure. When the piston rings fail, the engine consumes oil at an accelerated rate — far beyond what any manufacturer or owner would consider normal. The results included fouled spark plugs, rough idling, acceleration problems, performance loss, and in the most severe cases, complete engine failure.

The complaint alleged GM was aware of the defect as early as 2010. Internal company documents and engineer testimony introduced at trial showed GM had identified the piston ring problem before these vehicles reached consumers. GM continued selling the affected vehicles without disclosure. The lawsuit alleged concealment of a known defect — not simply a failure to discover one.

2016 — Lawsuit Filed in Northern District of California

The case was filed in 2016 in the U.S. District Court for the Northern District of California, case number 3:16-cv-07244-EMC, before Judge Edward M. Chen. The complaint was brought on behalf of LC9 engine owners who had experienced excessive oil consumption, engine damage, and repair costs they argued GM was responsible for covering.

2022 — Federal Jury Returns $102.6 Million Verdict

After years of litigation, the case reached trial. A federal jury returned a verdict of $102.6 million against General Motors. This was one of the rare automotive defect class actions to actually go to a jury verdict — most settle before trial. The verdict was a significant milestone and placed substantial pressure on GM to resolve the case.

October 2025 — $175 Million Settlement Approved

Following post-trial negotiations led by DiCello Levitt and co-counsel, the parties reached a settlement of $175 million. Judge Edward M. Chen approved the settlement in October 2025. The final amount represented a 22% increase over the jury’s original award — an unusual outcome where settlement exceeded verdict. Payments to eligible class members began in December 2025.

The settlement structure provided average payments exceeding $3,380 per vehicle for eligible class members. The three named plaintiffs who originally filed the lawsuit received $30,000 each. Attorney fees in the case totaled approximately $57 million. The settlement specifically covered owners in California, Idaho, and North Carolina, the three states where the specific state-law claims were concentrated. GM denied any wrongdoing as part of the settlement, as is standard in class action resolutions.

Who Is Eligible for the 5.3L LC9 Settlement

Eligible claimants are current or former owners and lessees of 2011–2014 GM vehicles equipped with the 5.3L V8 LC9 engine in California, Idaho, or North Carolina. The claims period for this settlement has closed. Payments began in December 2025 through the claims administrator. Former owners who sold their vehicles before the settlement was approved may also be eligible for a portion of the recovery.

Owners outside those three states are not covered by this settlement. Separate, smaller settlements were reached in other jurisdictions, including an Oklahoma case that paid the lead plaintiff $15,000 and other qualifying claimants $700 each.

Case 2: The 6.2L L87 V8 Lawsuit — Active Class Action

The second and ongoing lawsuit targets a different engine entirely: the 6.2-liter V8 EcoTec3 L87. This engine was introduced in 2019 and was installed in GM’s most expensive and most popular full-size trucks and SUVs. The defect is different from the LC9’s piston ring problem. The L87 issue involves the crankshaft and connecting rod bearings — components at the core of the engine’s rotating assembly — failing suddenly and catastrophically without warning.

The Defect: Crankshaft and Connecting Rod Bearing Failure

GM’s own recall documentation identified two root manufacturing defects in the L87 engine. First, rod-bearing damage caused by sediment contamination in connecting rods and crankshaft oil galleries. Second, out-of-specification crankshaft dimensions and surface finish — meaning the crankshaft was manufactured incorrectly. Both defects were traced to supplier quality failures during production. GM’s own recall report acknowledged the flawed manufacturing processes.

When these defects manifest, the result is loss of lubrication between the crankshaft and its bearings. Without lubrication, the metal components grind against each other under the enormous forces of engine operation. Drivers report a sudden, violent engine knock, immediate loss of propulsion, and in some cases engine fires. The failure can happen at any speed, including highway speeds, and often happens with no warning whatsoever. Engine failures have been documented in vehicles with as few as 1,200 miles on the odometer — and in one reported case, as few as four miles.

NHTSA’s field reporting database documented 1,157 engine bearing failure complaints tied to the L87 as of October 2025. GM received 28,102 internal complaints or incident reports by April 2025. More than 14,000 of those involved a loss of propulsion. The complaint documents 12 crashes, 42 fires, and 12 injuries associated with L87 engine failure.

January 2025 — NHTSA Opens Formal Investigation

NHTSA’s Office of Defects Investigation opened a formal probe into the L87 engine in January 2025 following reports of engine seizures and catastrophic breakdowns. On February 12, 2025, NHTSA issued a formal request to GM for documents, warranty records, and internal testing data. GM’s response cited “the sheer volume of data that needs to be assessed for over a million vehicles that span six model years.”

The investigation documented that owner complaints about the L87 had been circulating online for years before regulators acted. NHTSA’s formal inquiry put legal pressure on GM to act. It did, but the action it chose became its own legal problem.

February 2025 — First Lawsuits Filed

The first federal class action over the L87 engine was filed in February 2025 in the U.S. District Court for the Eastern District of Michigan. Lead plaintiff James S. Powell II alleged that the 2023 GMC Yukon Denali he purchased came equipped with the defective L87 V8 engine. Between February and November 2025, eleven separate class action lawsuits were filed in federal courts across the country, each making substantially similar allegations about the same manufacturing defects.

April–May 2025 — GM Issues Recall 25V-274

Under pressure from NHTSA’s investigation and mounting litigation, GM initiated NHTSA Recall 25V-274 in April 2025, formally announced on May 1. The recall covered approximately 597,630 vehicles in the United States — and over 720,000 vehicles globally — equipped with the 6.2L L87 V8 engine from model years 2021 through 2024.

The recall instructed dealers to inspect each vehicle using diagnostic trouble code P0016. Vehicles that triggered the code received a full engine replacement. Vehicles that did not trigger the code received a different remedy: drain the factory-specified 0W-20 oil, refill with heavier GM Dexos R 0W-40 synthetic oil, install a new oil filter, and install a new oil fill cap specifying the new oil requirement. GM also extended the warranty coverage for affected vehicles to 10 years or 150,000 miles. Owner notification began in June 2025.

The recall’s two-track approach immediately drew criticism. Plaintiffs’ attorneys and affected owners argued that the oil-change remedy for vehicles that did not trigger the diagnostic code was a “band-aid” that did nothing to address the underlying manufacturing defects. The defective crankshaft components and sediment contamination remained inside the engine. The heavier oil, critics argued, merely delayed failure rather than preventing it — potentially pushing the engine past its warranty period before breaking down entirely.

October 2025 — NHTSA Opens Second Probe

NHTSA’s Office of Defects Investigation opened a second probe on October 23, 2025, specifically to examine reports of engine failures in L87-equipped vehicles that were outside the scope of Recall 25V-274. The agency documented 173 incidents of engine failure in vehicles not included in the original recall. This suggested the defect extended beyond the 2021–2024 model years the recall addressed, into 2019 and 2020 models as well.

November 2025 — Additional Individual Lawsuits Filed

New individual lawsuits continued to be filed through late 2025. Illinois plaintiff Ronald S. Hermanowicz filed a lawsuit seeking $5 million in November 2025, alleging GM knowingly sold vehicles with defective L87 engines and had been aware of the bearing failures since at least 2021. The complaint cited the NHTSA investigation, the volume of consumer complaints, and GM’s recall as evidence of the company’s prior knowledge.

December 2025 — Lawsuits Consolidated in Eastern District of Michigan

With eleven separate class actions pending across multiple federal courts, GM and the plaintiffs agreed to consolidate the cases in the Eastern District of Michigan. A federal judge consolidated the actions into a single proceeding and appointed lead counsel from four major law firms: Hagens Berman, along with co-lead counsel firms to manage the unified litigation. The case was designated Rittereiser et al. v. General Motors LLC. Other overlapping filings proceeded under the caption Houchin et al. v. General Motors LLC, case number 2:25-cv-11462.

January 2026 — NHTSA Opens Recall Query RQ26001

NHTSA escalated its scrutiny further by opening Recall Query RQ26001 — a direct investigation into the adequacy of GM’s recall remedy. The query was triggered by 36 separate complaints in which L87 engines failed catastrophically after a dealer had performed the recall inspection and service. These owners had gone through the recall process, been told their engine passed, received the oil change remedy, and then experienced complete engine failure anyway. The NHTSA query asked the fundamental question the plaintiffs had been raising since the recall was issued: does the fix actually work?

February 26, 2026 — Consolidated Complaint Filed

Plaintiffs filed the consolidated class action complaint on February 26, 2026. The filing was 389 pages and named dozens of plaintiffs from across the United States. It outlined all claims against GM in detail and sought damages on behalf of everyone who purchased or leased an affected vehicle. Hagens Berman, led by attorneys Steve W. Berman and Shelby R. Smith, was named interim co-lead counsel for the consolidated action.

The complaint alleged GM manufactured engines with defective crankshafts and connecting rod bearings, knew about the defects, failed to disclose them at the point of sale, issued an inadequate recall remedy, and left hundreds of thousands of owners with vehicles that continued to pose safety risks. It sought compensation for out-of-pocket repair costs, diminished vehicle value, higher fuel costs from the thicker required oil, economic losses from loss of use, and punitive damages for GM’s alleged concealment of the known defect.

March 1, 2026 — Consolidated Litigation Officially Commences

The consolidated class action officially commenced in federal court in the Eastern District of Michigan on March 1, 2026. As of May 2026, the case is in the early litigation phase. Discovery has not yet produced documents. Class certification has not yet been sought. No settlement has been announced. The litigation timeline for a case of this complexity typically spans two to four years from commencement to resolution.

Affected Vehicles: Who Is Covered

The active L87 6.2L class action covers U.S. owners and lessees who purchased or leased the following GM vehicles equipped with the 6.2-liter V8 L87 engine:

NHTSA’s investigation has also documented failures in 2019 and 2020 model years outside the scope of the initial recall. The consolidated complaint encompasses 2019 through 2024 model years broadly. Attorneys are also evaluating whether 2025 model year vehicles with the L87 may be affected, as complaints from those vehicles have begun emerging.

GM has stated that manufacturing improvements implemented on or before June 1, 2024 addressed the contamination and quality issues at the root of the defect. That claim is contested by plaintiffs and remains a central factual dispute in the litigation.

What GM Has Argued

GM has not issued a public response to the consolidated complaint. In earlier filings and through its recall documentation, GM characterized the April 2025 recall as a significant and appropriate response to the failure pattern. The company argued that the two-track remedy, engine replacement for vehicles with confirmed defect codes and an oil specification change for others, was a responsible and proportionate fix.

GM told GM Authority that the manufacturing improvements introduced before June 2024 resolved the root cause of the crankshaft and connecting rod defects. The company’s position implies that post-2024 vehicles are not affected and that the recall addressed the extent of the problem in earlier model years. Plaintiffs dispute both claims, pointing to the NHTSA investigation into post-recall failures as evidence that the remedy is inadequate.

The Recall That Wasn’t Enough

The central allegation of the active L87 lawsuit is not just that GM sold defective engines. It is that GM’s own recall failed to fix them. The pattern of failure after recall service is the lawsuit’s most damaging factual thread.

NHTSA’s Recall Query RQ26001, opened in January 2026, is a federal agency asking out loud whether a manufacturer’s recall actually works. That is not a routine proceeding. It is a signal that regulators share the plaintiffs’ core concern. Thirty-six documented engine failures after recall service is a sample. Given the volume of vehicles involved, the true number of post-recall failures is likely higher.

The oil-change remedy that GM applied to engines that did not trigger diagnostic code P0016 is the practical flashpoint. Those engines were not replaced. They received different oil and a new cap. The manufacturing defects, the out-of-spec crankshaft dimensions, the sediment in the oil galleries, remained. The heavier oil may reduce the rate at which those defects cause bearing failure. It does not remove the defective parts. Plaintiffs argue this is the automotive equivalent of putting a fresh coat of paint on a cracked foundation.

How to File a Claim or Join the Lawsuit

For owners of 2011–2014 GM trucks and SUVs with the 5.3L LC9 engine in California, Idaho, or North Carolina: the Siqueiros settlement claims period has closed. Eligible owners who filed claims are receiving payments through the settlement administrator. If you were eligible and did not file in time, contact class counsel to determine whether any options remain.

For owners of 2019–2024 GM trucks and SUVs with the 6.2L L87 engine: the active class action is in early litigation. No settlement has been reached. Class members do not need to take immediate action to be included in a class action, but documenting your situation now is strongly advised. Owners should keep all repair orders, dealer service records, correspondence from GM, and documentation of any symptoms or failures. Owners who paid out of pocket for L87 engine repairs before the recall must submit reimbursement requests to their dealer by May 31, 2026, under the terms of GM’s special coverage warranty extension.

Owners who want to pursue individual lemon law claims rather than waiting for the class action should contact a lemon law attorney in their state. Individual claims may produce larger recoveries than class action settlements but require more active participation and legal representation.

What This Lawsuit Teaches Consumers

General Motors sold nearly 600,000 trucks and SUVs in the United States with engines its own engineers knew were manufactured out of specification. The crankshaft dimensions were wrong. The oil galleries contained sediment. These are not subtle design trade-offs discovered years later in the field. These are manufacturing defects that existed before the engine left the factory.

The pattern here is familiar. An automaker identifies a problem internally, conducts investigations it quietly closes, continues selling the affected vehicles, and issues a recall only when federal regulators force the issue. The recall remedy, designed to minimize cost and maximum coverage, turns out to be inadequate for a significant subset of affected vehicles. Then the lawsuits come.

The settled 5.3L LC9 case took nine years from filing to final settlement. The $175 million figure sounds large. Divided among more than 40,000 eligible owners, it averages around $3,380 per vehicle. Attorney fees were $57 million. The lawyers did well. The owners got something, though most would have preferred GM simply sell them a vehicle without a defective engine in the first place.

The 6.2L L87 case is just beginning. The vehicles affected are among GM’s most expensive: Escalades, Tahoes, Yukons, and top-trim Silverados and Sierras that retail for $60,000 to over $100,000. When an engine that costs that much fails at 1,200 miles, with no warning, on the highway, the economic and safety stakes are serious. Owners who experience sudden engine failure at speed are not just facing a repair bill. They are facing a genuine safety event. Courts and juries tend to respond accordingly.