GReddy 13901104 Sports Oil Filter OX-04 – FA20, Subaru EJ, Nissan, Honda & Mazda

GReddy 13901104 Technical Specifications

GReddy OX-04 Fitment – Which Engines Does It Fit?

GReddy lists the OX-04 for multiple Japanese engine families.

Important: These are manufacturer-listed engine families, not a guarantee that every vehicle using those engines accepts this filter. Verify the original filter specifications, thread, gasket diameter, clearance, and any engine-specific filtration requirements before ordering.

GReddy OX-04 for Subaru BRZ, Scion FR-S and Toyota 86

The naturally aspirated 2.0-liter FA20 boxer engine found in the first-generation Subaru BRZ, Scion FR-S, and Toyota 86 is a popular platform for performance driving and modification.

Its high-revving character and compact boxer layout make proper oil maintenance especially important.

The GReddy OX-04 is listed for the FA20 and Scion 4U-GSE applications, making it a suitable candidate for owners looking for a performance-oriented replacement oil filter.

Common First-Generation Applications

• 2013–2020 Subaru BRZ 2.0L FA20
• 2013–2016 Scion FR-S 2.0L 4U-GSE
• 2017–2020 Toyota 86 2.0L 4U-GSE

These applications should be confirmed against the vehicle’s existing filter specifications and GReddy’s application information.

For owners maintaining or modifying the BRZ/FR-S platform, proper oil filtration is one part of a larger engine maintenance strategy.

Why Double-Pleated Filtration Matters

Oil filters contain media that captures contaminants as oil circulates through the engine.

GReddy uses a double-pleated folding design to increase the available filtration surface within the OX-series filter.

More usable filtration area can help provide contaminant-holding capacity while supporting oil flow, depending on the media and filter design.

However, the manufacturer does not publish a verified micron efficiency rating or comparative filtration percentage for this product.

That means the OX-04 should not be advertised as filtering a specific percentage of particles or outperforming every OEM filter without supporting test data.

The practical advantage is GReddy’s engineered double-pleat construction and compatibility with selected performance engines.

Does a Performance Oil Filter Extend Engine Oil Life?

A high-quality oil filter can help keep circulating oil cleaner by capturing suspended contaminants.

But it cannot reverse oil oxidation, restore depleted additives, remove fuel dilution, or eliminate moisture contamination.

That means the GReddy OX-04 should not be advertised as automatically doubling oil life or allowing extended oil-change intervals.

For a detailed look at oil selection, viscosity, and engine protection, read our Is Synthetic Oil Better? What Your Engine Needs guide.

The best oil maintenance strategy combines the correct oil specification, a compatible filter, and service intervals appropriate for the engine and operating conditions.

Why Oil Filtration Matters on Turbocharged Engines

Turbocharged engines place additional demands on the lubrication system.

Engine oil lubricates critical internal components and, on oil-lubricated turbochargers, protects the turbocharger’s rotating assembly.

Contaminated oil can accelerate wear in sensitive engine components.

The GReddy OX-04 is listed for several popular turbocharged Japanese engine families, including Subaru EJ, Nissan SR, and Nissan VR38DETT applications.

For enthusiasts planning a complete turbocharged build, our Complete Street Turbo Build Guide explains why proper lubrication, cooling, and routine engine maintenance are essential.

An upgraded oil filter supports the maintenance side of the build, but it does not replace correct oil pressure, temperature control, or proper engine tuning.

GReddy OX-04 and Oil Cooler Compatibility

GReddy identifies the OX-04 as suitable for compatible GReddy oil cooler and oil filter relocation systems.

Its M20×1.5 thread makes it relevant to selected GReddy M20 remote oil filter blocks.

However, it is not interchangeable with GReddy’s 3/4-16 UNF filters.

For example, the GReddy 12401182 Type-I remote oil filter block uses an M20×1.5 filter mounting thread, while the GReddy 12401114 uses a 3/4-16 UNF filter thread.

These configurations require the correct filter.

Do not attempt to install an M20×1.5 oil filter onto a 3/4-16 UNF mounting stud.

How to Install the GReddy OX-04 Oil Filter

Replacing an oil filter is generally straightforward, but incorrect installation can lead to oil leaks or engine damage.

Step 1: Confirm Filter Compatibility

Verify the engine’s oil filter thread, sealing surface, and required filter specifications.

Step 2: Prepare the Vehicle

Park on a level surface and follow the manufacturer’s oil-change procedure.

Allow the engine to cool enough for safe service.

Step 3: Remove the Old Filter

Remove the existing oil filter and check that its sealing gasket has not remained attached to the engine.

Step 4: Prepare the New GReddy Filter

Inspect the new filter gasket and lightly lubricate it with clean engine oil if specified by the filter installation instructions.

Step 5: Install the Filter

Thread the filter on by hand, ensuring that it engages smoothly without cross-threading.

Tighten according to the manufacturer’s instructions.

Step 6: Refill and Inspect

Refill the engine with the correct oil quantity and specification.

Start the engine and inspect for leaks.

Confirm that oil pressure develops normally, shut the engine down, and recheck the oil level as directed by the vehicle manufacturer.

Frequently Asked Questions

What is GReddy 13901104?

It is the GReddy Sports Oil Filter OX-04, a spin-on oil filter using double-pleated filtration media.

Does the GReddy OX-04 fit the Subaru BRZ FA20?

Yes. GReddy lists the FA20 engine family among its OX-04 applications.

Does it fit the Scion FR-S and Toyota 86?

Yes. GReddy lists the Scion 4U-GSE engine, which is used in the first-generation FR-S and Toyota 86.

What thread size does it use?

M20×1.5.

How tall is the GReddy OX-04?

Approximately 65mm.

Does it fit the Subaru EJ20 and EJ25?

GReddy lists these engine families, but vehicle-specific compatibility must still be verified.

Does it fit a Nissan SR20DET?

GReddy lists compatible black-top SR applications. Verify the filter mounting configuration.

Does it fit a Nissan GT-R R35?

GReddy includes the VR38DETT engine in its application chart.

Does it contain a magnet?

Some retailers advertise magnetic particle collection, but the official GReddy OX-04 description reviewed here does not confirm a magnetic filtration element. Do not advertise one without manufacturer verification.

Will it increase horsepower?

No. An oil filter is an engine maintenance component, not a horsepower-producing modification.

Can it extend oil-change intervals?

No extended service interval is specified by GReddy. Follow the engine manufacturer’s maintenance requirements and adjust for severe operating conditions.

Protect Your Performance Engine With GReddy

The GReddy 13901104 Sports Oil Filter OX-04 combines double-pleated filtration media with a compact M20×1.5 spin-on design for compatible Japanese performance engines.

From the Subaru FA20 and EJ series to selected Nissan, Mazda, and Honda applications, the OX-04 provides an option for enthusiasts who want genuine GReddy filtration technology as part of their regular engine maintenance.

Choose the GReddy OX-04 for your next oil change when your engine requires its specific thread, sealing dimensions, and filter configuration.