Parts for your 2020 Mazda 3-Transmission filter

2020 Mazda 3 transmission filter: what’s actually fitted and what to service

For the 2020 Mazda 3 (BP series), a replaceable transmission filter isn’t a service item. Technical references including the Mazda3 BP Workshop Manual (SKYACTIV-Drive 6-speed automatic), Mazda Owner’s Manual maintenance schedules, and Aisin SKYACTIV-Drive design notes show the 6-speed automatic uses an internal, non-serviceable suction strainer and magnets inside the case, rather than an external, replaceable filter. There’s no removable transmission pan on this unit, and Mazda does not list a transmission filter replacement in routine servicing. Manual models don’t use a transmission filter at all.

Why no serviceable filter? The SKYACTIV-Drive automatic (often referenced as FW6A/AW6-series) is a tightly packaged, split-case design assembled in clean conditions with very fine clutch and valve body tolerances. It relies on Mazda Genuine ATF FZ and an internal mesh strainer plus case magnets to capture wear particles. Because the strainer lives inside the transmission and the case has no conventional pan, replacing it is only considered during an overhaul—well beyond normal maintenance. Mazda’s service literature also indicates no scheduled ATF or filter change under normal driving in many markets, reflecting the unit’s design philosophy.

That said, fluid condition still matters. For harsh use—lots of stop–start city work, frequent hill climbs, high ambient heat, spirited driving, or ride-share/taxi duty—an ATF inspection and a conservative drain-and-fill every 60,000–90,000 km can help longevity. Always use Mazda ATF FZ, and have the level set using the factory temperature procedure (a scan tool is typically needed). Full “power flushes” aren’t recommended on these units. If shifting feels harsh, delayed, or flares, a professional diagnostic and fluid check is smarter than guessing at a filter replacement that doesn’t exist as a service part.

• Transmission type: SKYACTIV-Drive 6-speed automatic with internal strainer, 6-speed manual has no filter.
• Service focus: fluid health, correct ATF (FZ spec), proper fill/level by temperature, cooling system condition.
• When to act: under severe use, consider periodic ATF drain-and-fill, otherwise follow Mazda’s inspection guidance.

For owners chasing reliability in Aussie and Kiwi conditions, keeping the ATF clean, shifts smooth, and the cooler circuit healthy does more than any “filter change” claim. If a workshop suggests a filter replacement on a 2020 Mazda 3 automatic, it’s worth asking which part they mean—because the factory filter isn’t a routine service item.

FAQs

Does a 2020 Mazda 3 have a transmission filter that needs replacing?
The 2020 Mazda 3 automatic uses an internal suction strainer and magnets, not a serviceable external filter. Mazda’s workshop and maintenance documentation don’t specify a routine filter change, the internal strainer is only accessed during overhaul. Manual models don’t have a transmission filter.

When should the automatic transmission fluid be changed on a 2020 Mazda 3?
Under normal driving, Mazda doesn’t list a scheduled ATF change in many markets. In tougher conditions—heavy traffic, hot climates, frequent hills, or ride-share duty—a precautionary drain-and-fill around 60,000–90,000 km is sensible. Always use Mazda ATF FZ and have the level set via the temperature-based procedure.

Can an aftermarket external transmission filter be added?
It’s generally not recommended. Plumbing in an auxiliary filter can affect flow and pressure, risks warranty or reliability concerns, and isn’t required by Mazda. Proper ATF, correct level, and sensible service intervals provide the intended protection on the SKYACTIV-Drive unit.