Migliaccio & Rathod LLP is investigating Purolator oil filters that may contain defective “louvers” inside the filter core, restricting oil flow and potentially causing engine wear or damage.

Reported Issues

Automotive enthusiasts, independent reviewers, and teardown channels have documented that certain Purolator filter lines – including Purolator One, Purolator Boss, and various private-label variants – contain partially closed or malformed louvers in the center tube. Reported defects include:

Louvers that are crushed, bent, or nearly sealed shut, significantly restricting oil passage
Filters entering constant bypass mode, reducing filtration effectiveness
Engines experiencing low oil pressure, premature wear, or abnormal noises shortly after oil changes
Wide variability in louver quality across production batches, suggesting manufacturing or process-control issues

These defects are hidden unless the consumer cuts the filter open.

Why Consumers Should Be Concerned

Restricted oil flow can deprive an engine of proper lubrication, leading to:

Accelerated bearing wear
Increased internal friction
Potential catastrophic engine failure
Costly repairs far exceeding the price of the filter itself

If Purolator sold filters with a known louver-manufacturing problem while advertising “maximum protection,” consumers may have claims under:

Implied warranty of merchantability
False advertising / UDAP statutes
Design or manufacturing defect theories

Signs You May Be Affected

Purchased Purolator oil filters (Purolator One, Boss, Classic, or store-brand variants) since 2019
Experienced low oil pressure, ticking/knocking noises, or engine performance issues soon after an oil change
Cut open your filter and observed restricted or malformed louvers
Had to pay for engine repairs that a mechanic linked to oil starvation or filter failure
Noticed repeated bypass-mode behavior or abnormal oil-pressure patterns

If you experienced these issues, fill out the form below or contact [email protected] or (202) 470-3520.

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Please briefly describe the issue with the product or service and when it occurred.

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