Protec PXA42728 Engine Air Filter

Engine Air Filter Overview

Protec PXA42728 is an engine air filter for everyday driving conditions, built as a panel-style replacement with cellulose media. It is engineered to match original equipment media area and is tested to ISO 5011 standards for filtration efficiency.

Key Features

• Panel-style engine air filter for routine service intervals
• Cellulose filter media for standard air intake filtration
• Matches original equipment media area
• Laboratory tested to ISO 5011 with 97.5% minimum efficiency
• Closed top inner diameter design

Detailed Description

The Protec PXA42728 engine air filter is a direct replacement air filter element for Subaru applications that use a panel-style filter. It is designed for normal driving conditions and uses cellulose media to help maintain clean intake airflow during a traditional service interval. The PXA42728 is a fitment-based replacement for 2000-2004 Subaru Forester, 1999-2004 Subaru Impreza, 1999-2004 Subaru Legacy, 2000-2004 Subaru Outback, and 2003-2006 Subaru Baja. This part cross-references Wix 42728 and Baldwin PA4128 for the same application.

What It Is Used For

• Replacing a restricted or dirty engine air filter
• Restoring normal intake airflow through the filter element
• Addressing reduced filtration performance from a worn filter
• Supporting routine maintenance on Subaru Forester, Impreza, Legacy, Outback, and Baja models

Installation Notes and Tips

Verify the existing filter size and panel style before installation. Confirm the air box accepts a closed-top panel filter with the listed dimensions: 14.586 inches long, 6.633 inches wide, and 1.358 inches high. Compare the old filter to the new one before closing the air box.

Quality Assurance

Protec states that this filter is tested to ISO 5011 standards and offers 97.5% minimum efficiency based on laboratory testing. The PXA42728 is built to match original equipment media area for consistent service replacement.