General Motors is facing or has recently resolved several large consumer class action lawsuits, most of them centered on alleged defects in transmissions, engines, fuel pumps, and batteries in Chevrolet, GMC, and Cadillac vehicles. The biggest active case covers more than 800,000 owners of trucks and SUVs with eight-speed automatic transmissions, and separate settlements in the past year have paid out for defective V8 engines, Duramax diesel fuel pumps, and Chevrolet Bolt EV batteries. GM has denied wrongdoing in each matter.
Eight-Speed Transmission Class Action
The largest pending case against GM is Speerly v. General Motors, LLC, consolidated in the U.S. District Court for the Eastern District of Michigan under Case No. 2:19-cv-11044. Owners of 2015–2019 vehicles equipped with the Hydra-Matic 8L90 or 8L45 transmission say the units shudder, jerk, hesitate, and lurch, and that internal problems send metal shavings through the transmission until it fails. Plaintiffs allege GM knew about the defect as early as 2015 and issued thirteen versions of a technical service bulletin while instructing dealers to tell customers the behavior was “normal” or “operating as designed.”1Cohen Milstein. Sixth Circuit Affirms Class Certification Against GM in Massive Defective Transmission Lawsuit
Affected models include the Chevrolet Silverado, Corvette, Camaro, and Colorado; the GMC Sierra, Yukon, Yukon XL, and Canyon; and the Cadillac Escalade, CTS, and CT6, in various model years between 2015 and 2019.2Justia. Speerly v. General Motors LLC, No. 23-1940
Class Certification Reversed En Banc
The district court certified 26 statewide classes on March 20, 2023, covering more than 800,000 owners.3Cohen Milstein. General Motors Litigation A Sixth Circuit panel affirmed on August 28, 2024, holding that alleging overpayment for a defective product was enough to establish standing.2Justia. Speerly v. General Motors LLC, No. 23-1940
On June 27, 2025, the full Sixth Circuit reversed in a 9–7 en banc ruling authored by Chief Judge Sutton. The majority found the district court had not conducted a sufficiently rigorous, element-by-element analysis of the 59 state-law claims and sent the case back for a state-by-state, claim-by-claim reassessment of commonality and predominance.4Quinn Emanuel. Quinn Emanuel Obtains Landmark En Banc Opinion Setting Important Class Action Precedent5Ballard Spahr. One Size Fits None: Sixth Circuit Demands State-by-State Analysis in Auto Defect Class Actions Legal observers have said the broad multi-state class is unlikely to survive in its original form.
Companion Case for Other States
Ulrich v. General Motors (Case No. 2:24-cv-11007), filed April 17, 2024 in the same court, covers owners in ten states that were not part of Speerly: California, Connecticut, Indiana, Iowa, Massachusetts, Missouri, North Dakota, Oregon, Rhode Island, and South Dakota. On June 13, 2025, the district court denied GM’s motion to compel arbitration, holding that dealership purchase-agreement arbitration clauses do not cover GM because the manufacturer is not a party to those contracts.6Cohen Milstein. Second Class Action Filed Against General Motors for Defective Transmissions3Cohen Milstein. General Motors Litigation Ulrich has not yet reached class certification.
LC9 V8 Engine: $150 Million Settlement
A separate line of cases targeted the Generation IV Vortec 5300 LC9 5.3-liter V8 in 2011–2014 Chevrolet Avalanche, Silverado, Suburban, and Tahoe models and 2011–2014 GMC Sierra, Yukon, and Yukon XL. Owners alleged the piston assemblies caused premature ring failure, excessive oil consumption, and engine damage.7GM Engine Litigation. Siqueiros et al. v. General Motors LLC
In Siqueiros v. General Motors LLC (Case No. 3:16-cv-07244-EMC, N.D. Cal.), a jury in October 2022 found that GM concealed the defect and awarded roughly $102.6 million, about $2,700 per class member, to some 38,000 owners in California, Idaho, and North Carolina.8CNBC. GM Hit With $102.6 Million Jury Verdict in Engine Flaw Class Action The court denied GM’s motions to set the verdict aside. The parties then settled for $150 million. Judge Edward M. Chen granted final approval on October 8, 2025, and payments began in late December 2025, with each eligible owner receiving at least $2,149 after fees and costs.9GM Engine Litigation. FAQs – Siqueiros et al. v. General Motors LLC
An Oklahoma companion case, Hampton v. General Motors LLC (Case No. 6:21-cv-250-GLJ), settled for approximately $24.8 million, with final approval on September 15, 2025. About 30,000 vehicles were estimated to qualify, with individual payouts around $500.10Oklahoma GM Engine Litigation. Hampton v. General Motors LLC Settlement11KFOR. Some Oklahoma Car Owners Could Get $500 Through Class Action Settlement
Duramax CP4 Fuel Pump Settlement
Owners of 2011–2016 Chevrolet Silverado and GMC Sierra heavy-duty trucks with the 6.6L Duramax diesel sued over the Bosch CP4 high-pressure fuel pump, alleging it was incompatible with U.S. diesel fuel and prone to failures that sent metal shavings through the fuel system. In Chapman v. General Motors LLC (Case No. 2:19-cv-12333-TGB-DRG), Judge Terrence G. Berg granted final approval to a $50 million settlement on May 6, 2025.12HBS Law. CP4 Fuel Pump Defect – GM, Ford
The settlement set aside $30 million for owners who paid out of pocket for fuel pump repairs and $5 million for former owners who sold before repairs, and it created a one-year program covering 50 percent of future CP4 repair costs at GM-authorized dealerships that ran through May 2026. Initial checks went out in March 2026.13GM Fuel Pump Litigation. Chapman v. General Motors LLC – FAQ
Chevrolet Bolt EV Battery Settlement
Owners of 2017–2022 Chevrolet Bolt EVs alleged that the lithium-ion batteries posed a fire risk when charged to full or near-full capacity, leading to two NHTSA recalls covering about 109,000 vehicles. In In re Chevy Bolt EV Battery Litigation (Case No. 2:20-cv-13256), Judge David M. Lawson granted final approval to a $150 million non-reversionary settlement.14GM Authority. Chevy Bolt Battery Settlement Reaches Final Approval
Rather than large cash payments, the settlement placed GM’s battery remediation program under court supervision. Owners whose battery modules were replaced received $700; those who received GM’s diagnostic software remedy received $1,400. About 22,560 vehicles received the software fix, which caps charging at 80 percent during an initial monitoring period and alerts the driver of anomalies. Owners who had already accepted a GM buyback were excluded.15Bolt EV Battery Settlement. Frequently Asked Questions
L87 Engine Failure Litigation
The newest major case targets GM’s 6.2L V8 L87 engine. Plaintiffs allege manufacturing defects in the connecting rod and crankshaft can cause sudden, catastrophic failure without warning. NHTSA opened an investigation in January 2025, and GM issued a recall in April 2025 covering nearly 600,000 vehicles, including 2019–2024 Chevrolet Silverado 1500 and GMC Sierra 1500 trucks and various 2021–2024 SUVs. The consolidated litigation, Rittereiser v. General Motors (Case No. 4:25-cv-11481), is pending in the Eastern District of Michigan, where interim class counsel was appointed in November 2025.16HBS Law. General Motors L87 Motor Engine Failure Defect
Other GM Cases Worth Knowing About
Shift to Park Defect
Jefferson v. General Motors and Riley v. General Motors settled claims that certain 2016–2019 models, including the GMC Acadia, Chevrolet Blazer, Malibu, Traverse, and Volt, displayed a “Shift to Park” message while already in park, sometimes preventing shutoff and draining the battery. The settlement paid $500 to qualifying Ohio and Tennessee owners who sought warranty repairs and up to $375 in out-of-pocket reimbursement, with a final fairness hearing set for August 22, 2025.17CarComplaints. GM Shift to Park Class Action Lawsuit Settlement
Chevy Shake Driveshaft Cases
Weiss v. General Motors and Bostick v. General Motors (Case No. 5:19-cv-02451, C.D. Cal.) allege aluminum driveshafts in 2014–2019 Silverado and Sierra trucks cause severe highway-speed vibrations that can worsen and lead to loss of control. Nationwide class certification was denied in Weiss in late 2019, but the case moved forward for Florida customers.18Autobody News. Chevy Shake Class Action Says Driveshaft Is the Problem
OnStar Data Sharing
In January 2025, the FTC announced a proposed consent order banning GM and OnStar from disclosing precise geolocation and driving-behavior data to consumer reporting agencies for five years and requiring affirmative consumer consent before collecting connected-vehicle data. The claim was that GM’s “Smart Driver” feature shared data with LexisNexis and Verisk, which sold it to insurers.19FTC. FTC Takes Action Against General Motors for Sharing Drivers Precise Location and Driving Behavior Data
Ignition Switch Settlement
GM’s earlier ignition switch defect was linked to at least 124 deaths and 275 injuries. In October 2017, GM agreed to a $120 million settlement with the attorneys general of 49 states and the District of Columbia to resolve consumer protection claims. That deal was separate from federal multi-district litigation and a disputed $1 billion claims resolution process. Earlier in 2017, the U.S. Supreme Court declined to hear GM’s appeal, allowing suits over pre-bankruptcy accidents to proceed.20Detroit Free Press. GM Ignition Switch Settlement21HBS Law. General Motors Ignition Switch
What Owners Can Do
Owners of any of the affected models should check the settlement administrator websites for their specific case for deadline and eligibility details, keep repair records, and confirm whether their vehicle falls within the model years and states covered. Coverage varies by case: Speerly is unsettled and now being reassessed state-by-state, Ulrich is limited to ten specific states, and the Bolt, LC9, and CP4 settlements have already begun paying out under their own rules.