Harrison et al. v. General Motors LLC is a pending class action filed in the United States District Court for the Eastern District of Michigan (Case No. 2:21-cv-12927-LJM-APP).
The complaint alleges defects in AFM/DFM valve train systems in certain 2014–present Buick, Cadillac, Chevrolet, and GMC vehicles. Owners report engine problems such as misfires, loss of power, stalling, and shuddering that may create safety risks and warranty issues.
NHTSA has opened a preliminary review into some 2019–2024 trucks and SUVs equipped with the L87 V8 after engine failure complaints. General Motors is cooperating with the agency while owners seek clarity on coverage and repairs.
This page provides a clear, current overview of the case, which engines and vehicles may be affected, common warning signs, and practical steps consumers can take now.
Key Takeaways
- The case Harrison et al. v. General Motors LLC is pending in the Eastern District of Michigan.
- Alleged defects involve AFM/DFM valve train systems in select V8 engines and model years.
- Reported symptoms include misfires, hesitation, loss of power, and Check Engine Light alerts.
- NHTSA is investigating reported engine failures in 2019–2024 L87-equipped trucks and SUVs.
- Document symptoms, save service records, and consider legal counsel or warranty remedies.
Overview of the GM Active Fuel Management Lawsuit
This section summarizes the core allegations and the technical theory at the heart of the case. It explains why specialized lifters and related valve train systems are central to claims about engine performance and safety.
Harrison et al. v. General Motors LLC in the United States District Court for the Eastern District of Michigan
Harrison et al. v. General Motors LLC (Case No. 2:21-cv-12927-LJM-APP) is pending in the district court eastern division for the Eastern District of Michigan. Plaintiffs allege defects in AFM/DFM-enabled V8 engines and seek to prove widespread failures across vehicles equipped with these systems.
What AFM/DFM is and how valve train systems factor into the case
Active fuel management and dynamic fuel management are systems designed to deactivate cylinders under light load to save fuel. These systems use specialized lifters that change how the valve train operates.
Plaintiffs claim that faulty lifters can stick or fail to actuate, disrupting valve train operation. That may cause misfires, hesitation, stalling, shuddering, and loss of engine power.
- Design focus: Lifters, pushrods, valve springs, and camshafts interact in real-world use.
- Alleged risk: Sudden performance loss can create safety concerns on roadways.
- Communications: General Motors issued service bulletins and extended coverage letters addressing lifter and valve train issues.
| Component | Function | Common Symptom | Notes |
|---|---|---|---|
| AFM/DFM lifter | Deactivates valves | Misfire / shudder | Alleged premature failure |
| Pushrod | Transmits cam motion | Loss of power | Interacts with lifter faults |
| Valve spring | Returns valve position | Noise / stalling | May be cited in diagnostics |
| Camshaft | Controls valve timing | Surging / hesitation | Central to technical evidence |
For ongoing case details and updates, readers can follow the docket and related notices. Review the site’s privacy policy for data practices.
Vehicles, Engines, and Systems Potentially Affected
Owners and lessees who purchased or leased 2014–2021 Buick, Cadillac, Chevrolet, or GMC models should verify whether their vehicle is within the scope. The class targets consumers purchased leased 2014–2021 models equipped with 5.3L, 6.0L, or 6.2L V8 engines featuring AFM/DFM cylinder deactivation.
Who is covered
Coverage broadly includes anyone who purchased or leased 2014–2021 vehicles with the noted V8s. Keep build dates and RPO codes handy for service checks.
Models frequently cited
- Silverado / Sierra (2014–2021)
- Tahoe, Suburban, Yukon, Yukon XL (2014–2021)
- Escalade, Corvette, Camaro, CTS‑V, Avalanche (select years)
Common defect indicators
Reported symptoms include tapping or ticking, knocking, misfires, shuddering, loss of power, stalling, and an illuminated Check Engine Light. Technical notes flag L84 5.3L and L87 6.2L builds from late 2020 to early 2021 and some vehicles produced June–Sept 2020 for valve spring checks.
Action: Document symptoms, save service records, and refer to the site’s privacy policy for how case data is handled.
GM Active Fuel Management Lawsuit: Allegations, Case Posture, and Key Documents
Plaintiffs claim that defective lifters and associated valve parts caused repeated engine failures, sudden loss of power, and safety risks in affected vehicles.
Core allegations
The complaint asserts the AFM/DFM lifters and the wider valve train system are defective in design or manufacture. Plaintiffs say these faults produce misfires, hesitation, shuddering, stalling, and in some cases, engine damage that requires costly repair.
Warranty and legal theory
The suit contends consumers were not warned and that omissions breached express and implied warranties and state consumer protection law. The pending class action lawsuit is litigating defect proof, class certification, and remedy scope.
Key GM documents and dealer guidance
General Motors LLC issued a Power Component Coverage Letter extending powertrain coverage in some cases to 60 months/100,000 miles. Dealer Service Bulletin steps include diagnosing misfires, checking for broken valve springs, and cylinder leakage tests.
For vehicles built June 1–September 15, 2020, guidance may require replacing all valve springs on both banks when criteria are met. Compare repair records with the coverage terms and the site’s privacy policy to evaluate eligibility and support for warranty or class claims.
NHTSA’s Current Probe into GM Engine Failures
NHTSA has launched a preliminary evaluation after early warning reports flagged serious failures in L87 V8 powerplants. The review covers roughly 877,710 trucks and SUVs from 2019–2024, including Silverado, Sierra, Tahoe, Suburban, Yukon, and Escalade models.
Scope of the investigation
The probe opened following 39 consumer complaints and manufacturer reports. Allegations include bearing failures that led to engine seizure and incidents where a connecting rod breached the engine block.
Potential outcomes and consumer impact
The agency may close the inquiry, expand it to an engineering analysis, or require a manufacturer recall or service campaign. A confirmed defect could accelerate repairs, extend coverage, and affect resale value.
- Document symptoms: note noises, warning lights, and loss of power.
- Save records: keep service invoices and communications for eligibility if remedies are announced.
- Monitor updates: General Motors has said it will cooperate; follow the investigation for changes to coverage or repair options.
| Item | Detail |
|---|---|
| Population | ~877,710 vehicles (2019–2024 L87 V8) |
| Complaints | 39 early reports of engine failures |
| Reported issues | Bearing failure, connecting rod breach, sudden loss of power |
Note: If your vehicle shows related symptoms, seek diagnosis promptly and retain records. Also review the site’s privacy policy for guidance on data and case updates.
Your Legal and Warranty Options in the United States
If your vehicle shows repeated valve train trouble, you have clear legal and warranty paths to consider.
Joining or tracking the class action
You can track or seek to participate in the class action pending in the Eastern District of Michigan. If the court eastern district certifies a class, you may receive notice with steps to join and claim relief.
Lemon law and warranty avenues
Consumers also retain individual remedies under the Magnuson‑Moss Warranty Act and state lemon laws. These laws can provide repurchase, replacement, or cash compensation when defects persist after reasonable repairs.
What to do next
Document everything. Keep service orders, dates, mileage, symptoms, and parts replaced. Note any Power Component Coverage Letters or dealer communications.
- Consult a consumer protection attorney about your repair history and jurisdiction.
- Reference the Harrison case when speaking with counsel and preserve records for potential action lawsuit or warranty claims.
- Schedule prompt diagnosis for misfires or loss of power and request detailed repair invoices.
Review the site’s privacy policy before submitting records or joining the class action lawsuit.
Conclusion
Takeaway: Owners and lessees should act promptly if their vehicle shows misfires, shuddering, loss of power, stalling, or unusual engine noise linked to AFM or valve train systems.
Harrison et al. v. general motors llc alleges defective afm/dfm lifters across certain V8 models. General motors issued extended coverage letters and dealer bulletins that outline diagnostics and repair paths for lifter and valve spring concerns.
NHTSA’s probe of L87 6.2L engine failures covering roughly 877,710 vehicles equipped active fuel systems remains ongoing.
Document symptoms, retain service records, seek prompt professional diagnosis, and consult counsel about warranty and state law options. This page will update as new court, coverage, or agency developments arise; review the privacy policy before submitting records.
FAQ
What is the Harrison et al. v. General Motors LLC case about?
The case alleges defects in certain lifters and valve train systems on select 5.3L, 6.0L, and 6.2L V8 engines installed in Buick, Cadillac, Chevrolet, and GMC vehicles. Plaintiffs claim these parts can fail, causing engine noise, misfires, loss of power, and related safety and warranty issues. The action is pending in the United States District Court for the Eastern District of Michigan.
Which vehicles and model years are potentially affected?
The class targets consumers who purchased or leased 2014–2021 vehicles equipped with the named V8 engines, including popular models such as Silverado, Sierra, Tahoe, Suburban, Yukon, Escalade, Camaro, and Corvette. Exact coverage can vary by engine code and production date, so owners should confirm with their VIN and service records.
What symptoms should vehicle owners watch for?
Common indicators include persistent engine ticking or knocking, frequent misfires, shuddering, sudden loss of power, stalling, and an illuminated Check Engine Light. These signs may point to failing lifters or other valve train components and warrant prompt inspection.
What are the main allegations against General Motors LLC in the complaint?
Plaintiffs allege that defective lifters and valve train components cause premature failure, present safety risks, and breach express and implied warranties. The complaint seeks remedies for repair costs, diminished value, and related damages under consumer protection and warranty laws.
Has the company issued any guidance or documents about these engine issues?
Automaker communications such as powertrain coverage letters and dealer service bulletin guidance have circulated addressing diagnosis and repair protocols. These documents may affect warranty coverage and repair timelines; affected owners should request copies from dealers or their legal counsel.
Is the National Highway Traffic Safety Administration investigating these engine failures?
Yes. The NHTSA opened a probe covering certain 2019–2024 trucks and SUVs with relevant L87 V8 engines. The investigation examines engine failures, safety risks, and whether recall action or other remedies are warranted.
How could the NHTSA probe affect owners?
Depending on findings, the agency could require a recall, demand remedy plans, or close the investigation without action. A recall would obligate the manufacturer to repair affected vehicles at no charge; otherwise, owners may need to rely on warranty or legal remedies.
Can I join the class action or track its status?
Affected consumers may be eligible to join the class or remain informed through court filings and counsel representing the class. Contact the lead plaintiff’s attorneys or check the Eastern District of Michigan docket for case updates and instructions on participation.
What warranty and legal options are available besides the class case?
Owners can pursue warranty claims under the vehicle’s express warranty, invoke protections under the Magnuson-Moss Warranty Act, or file state lemon law claims if the vehicle meets statutory criteria. Consulting an experienced attorney helps determine the strongest remedy for your situation.
What practical steps should I take if I experience valve train or lifter issues?
Document symptoms, service visits, and repair orders. Keep all receipts and diagnostic reports, obtain the vehicle identification number (VIN), and contact an attorney if repairs are denied or problems persist. Timely records strengthen warranty and legal claims.
Will repairs be covered if my vehicle is out of factory warranty?
Coverage depends on the manufacturer’s extended programs, any special powertrain coverage letters issued, and state laws. If no voluntary coverage applies, legal avenues such as the class case or Magnuson-Moss claims may provide recourse for out-of-warranty failures.
How can I verify if my vehicle is part of the affected group?
Verify your VIN with an authorized dealer, review service bulletins applicable to your model and year, and consult the class action notice or court docket. Attorneys representing plaintiffs can also help confirm eligibility based on engine codes and production dates.
