$102.6 Million Jury Verdict Over GM's Defective 5.3L Vortec V8 Engines
After trial: Later settled for $150 million.
Won by Beasley Allen.
A federal jury found General Motors liable for defective piston rings in its 5.3-liter Vortec V8 engines and awarded $102.6 million to a class of roughly 38,000 truck and SUV owners across three states.
What happened
For years, owners of GM light-duty trucks and SUVs equipped with the Generation IV 5300 LC9 engine reported the same problem: the engine burned through quarts of oil at a rate that no manufacturer specification could explain. The root cause, plaintiffs alleged, was a design flaw in the piston rings. Those rings failed to seal properly, allowing oil to migrate into combustion chambers and other parts of the engine where it did not belong. The result was accelerated wear, carbon buildup, and, in many cases, premature engine failure.
The class that eventually went to trial covered roughly 38,000 owners of 2011-2014 model-year trucks and SUVs sold in California, North Carolina, and Idaho. These were working vehicles: pickups and full-size SUVs that owners depended on for daily transportation, towing, and work. General Motors, the plaintiffs argued, knew about the oil-consumption problem and failed to disclose it at the time of sale.
Beasley Allen served as co-lead trial counsel alongside DiCello Levitt, litigating the case in the Northern District of California under Judge Edward M. Chen. The Beasley Allen team included Clay Barnett, Dee Miles, and Demet Basar. The trial teams argued that GM's own data showed the piston-ring defect caused oil to infiltrate parts of the engine where it had no business being, shortening engine life and leaving consumers with repair bills that should never have been theirs to bear.
The jury returned a verdict of $102.6 million in October 2022, one of the larger product-defect class awards in federal court that year. General Motors contested the result, but the litigation ultimately resolved in 2025 when a federal court granted final approval to a $150 million class settlement. That settlement covered the California, North Carolina, and Idaho classes and closed a case that had been pending since 2016.
The final approved settlement amount of $150 million exceeded the jury's award by roughly $47 million.
Sources
This account is drawn from contemporaneous public reporting and the court record.
- 1.CNBC - independent news coverage of the $102.6M jury verdict in Siqueiros v. General Motors LLC (October 2022)·Archived copy
- 2.Bloomberg Law - independent legal news reporting final approval of the $150M class settlement in October 2025
- 3.Top Class Actions - independent legal-news coverage naming H. Clay Barnett III of Beasley Allen as class counsel in Siqueiros v. General Motors LLC·Archived copy
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