How much oil does a WRX take?

It depends on the engine. The older EJ-series turbo (2002–2014 GD/GR) holds roughly 4.2–4.5 US quarts with a filter change. The FA20DIT in the 2015–2021 VA is closer to 5–5.4 quarts with filter. The 2022+ VB's FA24 is in the same 5-quart ballpark. These are planning figures — always fill to the dipstick's safe range rather than trusting a number, because a boxer's oil level reads differently depending on how level the car is and how long it's sat.

What weight oil does a WRX use?

Every FA-engine WRX (2015+) specifies a full-synthetic oil to Subaru's requirement — the VA's FA20DIT commonly runs 5W-30, and the newer VB's FA24 may call for a lighter grade, so go by the weight printed on your oil filler cap and in the manual. The older EJ turbo cars are generally 5W-30, with some owners stepping up to 5W-40 for hard, hot-weather, or tracked use. The cap is the source of truth for your specific car.

What fluid goes in a WRX manual transmission?

A GL-5 gear oil, typically 75W-90 — Subaru's own Extra-S is the OEM choice and many owners run a quality 75W-90 synthetic. The 5-speed holds roughly 3.5 quarts; the 6-speed a bit more, around 3.7–4 quarts. On manual cars the front differential shares the transmission case, so filling the gearbox fills the front diff too — one fluid, one job. Confirm your exact capacity in the manual before you drain.

What differential fluid does a WRX use, and how much?

The rear differential takes a GL-5 hypoid gear oil, usually 75W-90, and holds a small amount — roughly 0.8 quart. On manual-transmission WRXs the front diff is integrated into the transmission and shares that gear oil; on CVT automatic cars the front diff is separate with its own fluid. If your car has a limited-slip rear diff, check whether a friction modifier or an LSD-specific gear oil is called for.

What coolant does a WRX take?

Use Subaru's long-life coolant (the blue Subaru Super Coolant) or a compatible OEM-spec long-life formula — the aluminum boxer and its cooling passages are happiest on the coolant Subaru engineered for them, and mixing incompatible chemistries is a real way to cause corrosion or gelling. The full cooling system holds in the neighborhood of 7–8 quarts, but a drain-and-fill moves less. Always confirm type and capacity for your year; the boxer runs hot and a healthy, correct cooling system is part of fighting heat-soak.

Does a WRX have power steering fluid?

It depends on the generation, and this trips people up. The older EJ WRX (2002–2014 GD/GR) uses a hydraulic power-steering system with its own fluid to check and top up. The FA-era cars (2015+ VA and 2022+ VB) switched to electric power steering — there is no power-steering fluid to service at all. If you own a newer WRX and can't find a power-steering reservoir, that's why.

WRX Fluids & Capacities Reference: Oil, Gear Oil, Diff, and Coolant Specs by Generation

Ask a WRX owner “what oil does it take” and half the arguments in the forum come from people quoting the wrong engine. The WRX has worn three very different powertrains across its generations, and the fluids — weights, capacities, even whether a system has a fluid — change with them. This is the spec sheet: engine oil, gear oil, both differentials, coolant, brakes, and the power-steering split, organized so you can find your car and get the right fluid in the right hole in the right amount.

One rule before any number below: the figures here are for planning, not gospel. Fill engine oil and transmission fluid to their level checks, and confirm the exact capacity and specification for your model year in the owner’s manual or on the filler cap. Capacities shift slightly year to year, and the penalty for guessing on an AWD car is expensive. Not sure which WRX you’re standing in front of? Start with the WRX generations & fitment guide — engine family (EJ vs. FA, generation years confirmed on Wikipedia) is the fork that changes most of these answers. And for when to change each of these, this page’s companion is the WRX maintenance schedule & parts checklist.

Know your engine family first

Every answer below branches on which boxer you have:

EJ-series turbo (2002–2014, GD/GR chassis): EJ205/EJ255 2.0L and 2.5L turbo fours. Hydraulic steering, timing belt, the “classic” WRX driveline.
FA20DIT (2015–2021, VA chassis): 2.0L direct-injected turbo. Electric steering, timing chain.
FA24 (2022+, VB chassis): 2.4L direct-injected turbo. Electric steering, timing chain, the current car.

If you’re shopping used and don’t know the failure history behind these fluids, the common WRX problems by generation guide is worth a read first — several of the classic issues (oil consumption, contaminated clutch, cooked gear oil) show up as fluid problems.

Engine oil — the one everyone asks about

The heartbeat fluid, and the one where the engine family matters most.

Engine (chassis)	Viscosity (confirm on cap)	Capacity w/ filter (approx.)
EJ255 turbo (GD/GR, ‘02–‘14)	5W-30 synthetic (some run 5W-40 for hard use)	~4.2–4.5 US qt
FA20DIT (VA, ‘15–‘21)	5W-30 full synthetic to Subaru spec	~5–5.4 US qt
FA24 (VB, ‘22+)	Full synthetic per cap/manual (may be a lighter grade)	~5 US qt

A few WRX-specific notes the table can’t hold:

The cap wins. Subaru prints the required weight right on the oil filler cap. If your cap and a forum post disagree, the cap is correct for your car.
Measure, don’t pour blind. A cold boxer’s dipstick reads differently than a warm one, and overfilling a turbo motor is its own problem. Fill most of the way, run it, let it settle on level ground, then top to the safe range.
Filter every time. A genuine Subaru filter or a reputable equivalent at every change — the turbo runs the oil hot and a good filter is cheap.
Tuned or tracked? Hard-used and hot-climate cars are exactly where owners step an EJ up to 5W-40 or shorten the interval. Match the oil to how the car actually lives.

Price current oil, filters, and service parts in the maintenance category, or pull a genuine Subaru filter/service kit from the eBay Motors buttons on this page.

Manual transmission & front differential — one fill, on manual cars

This is the detail that surprises first-timers: on a manual WRX the front differential is inside the transmission case and shares its gear oil. Fill the gearbox and you’ve filled the front diff. One fluid, one drain plug, one fill plug.

Fluid: a GL-5 gear oil, typically 75W-90. Subaru’s Extra-S is the OEM answer; plenty of owners run a quality 75W-90 synthetic.
Capacity: the 5-speed holds roughly 3.5 quarts; the 6-speed a bit more, around 3.7–4 quarts.
Why it matters on a WRX: the gearbox lives behind a torquey turbo motor and gets abused on launches — tired, sheared gear oil shows up as notchy shifts and grinding into 2nd. If you’ve stepped up power and are thinking about the driveline, the clutch & flywheel upgrade guide covers what actually breaks first.

CVT automatic cars are different: the front diff is not shared with a manual case, and the transmission uses Subaru’s High-Torque CVT fluid — not something to improvise on, and not the gear oil above.

Rear differential — small, easy, skipped

The rear diff is its own sealed housing on every WRX and needs its own service.

Fluid: GL-5 hypoid gear oil, usually 75W-90.
Capacity: small — in the neighborhood of 0.8 quart.
LSD note: if your car has a limited-slip rear (STI and some WRX configurations), check whether a friction modifier or an LSD-specific gear oil is required — the wrong fluid in a clutch-type LSD causes chatter.

Because it’s AWD, remember the WRX has three gear-oil services living in the driveline — trans/front (on manuals), and the rear diff — plus the engine oil. It’s the tax for sending power to all four wheels, and skipping the diffs is how center-driveline wear starts.

Coolant — use Subaru’s, don’t mix chemistries

The aluminum boxer runs hot, and its cooling system is engineered around a specific coolant.

Fluid: Subaru long-life coolant (the blue Subaru Super Coolant) or a compatible OEM-spec long-life formula. Do not casually mix a different chemistry into the system — incompatible coolants can gel or promote corrosion in aluminum passages.
Capacity: the full system holds roughly 7–8 quarts, but a simple drain-and-fill moves noticeably less; a full flush is the only way to actually turn over the whole volume.
Why it matters: a healthy cooling system is half the battle against heat-soak — the same fight the intercooler guide is about on the intake side. Old, depleted coolant loses its corrosion inhibitors long before it looks dirty.

Grab genuine Subaru Super Coolant from the eBay Motors button on this page if your local counter is out.

Brake fluid — the one to move up the list if you track

Spec: a quality DOT 3 / DOT 4 brake fluid; step to a high-boiling-point DOT 4 (or a dedicated track fluid) if you see track time.
Why: brake fluid absorbs water over time and boils under hard, repeated braking — that’s the soft, sinking pedal on lap five. Fresh, high-boiling fluid is the cheapest fade insurance there is.

If you’re upgrading the brakes to go with harder driving, the brake upgrades guide and the brake pad types explainer cover the pads, lines, and fluid that belong together.

Power steering — the EJ-vs-FA split that confuses everyone

This is the one that sends people hunting for a reservoir that doesn’t exist:

EJ WRX (2002–2014, GD/GR): hydraulic power steering. There’s a pump, a reservoir, and a fluid to check and top up. Use the fluid Subaru specifies for the system.
FA WRX (2015+ VA and 2022+ VB): electric power steering. No hydraulic fluid at all — the assist is electric, so there is nothing to service. If your newer WRX has no power-steering reservoir, that’s by design, not a missing part.

Quick-reference fluid card

Confirm every spec and capacity against your owner’s manual — this is the pattern, not the last word:

Engine oil: EJ ~4.2–4.5 qt (5W-30, 5W-40 for hard use); FA20 ~5–5.4 qt (5W-30 synthetic); FA24 ~5 qt (per cap). Filter every change.
Manual trans + front diff (one fill): 75W-90 GL-5 (Subaru Extra-S); 5MT ~3.5 qt, 6MT ~3.7–4 qt.
Rear diff: 75W-90 GL-5, ~0.8 qt; check LSD friction-modifier need.
CVT (auto cars): Subaru High-Torque CVT fluid — OEM only.
Coolant: Subaru long-life (blue), ~7–8 qt full system; don’t mix chemistries.
Brake fluid: DOT 3/4; DOT 4 or track fluid if you lap the car; flush every ~2 years.
Power steering: EJ = hydraulic fluid to check; FA = electric, no fluid.

Where to buy the right fluids

New oil, filters, coolant, and brake fluid: the maintenance category is where to price current in-stock service fluids and parts on Amazon.
Genuine Subaru fluids and OEM service kits: eBay Motors is a smart-money source for genuine Subaru filters, Extra-S gear oil, and Subaru Super Coolant when your local dealer counter is dry — the buttons on this page pull live listings with real prices. Matching OEM chemistry matters most on coolant and CVT fluid, where substitutes cause real problems.

Get the fluids right and the rest of the car works the way it should — a healthy driveline is the quiet foundation under every intake, downpipe, and tune you bolt on top. When you’re ready to schedule all of this instead of just spec it, the maintenance schedule tells you how often.