Why is my Toyota GR Supra leaking coolant at the oil filter housing?

Short answer: GR Supra shares the BMW B58 plastic oil filter housing leak. Pressure-test, then replace the housing/gaskets—or upgrade to aluminum—before you chase a water pump blindly.

Symptom: Coolant loss, wetness at the oil filter housing, sweet smell, or oil/coolant mixing concerns on a B58 Supra.

What to check first

1. Pressure-test the cooling system cold and hot.
2. Inspect the plastic housing and cooler joint for crust or wetness.
3. Ask whether the shop replaces the full housing or only gaskets.
4. Watch oil for milky signs if coolant and oil may have mixed.

Likely causes

1. Plastic oil filter housing / gasket leak. The B58 plastic oil filter housing and gaskets can seep coolant (and sometimes oil). Owners discuss aluminum replacements.
2. Oil cooler interface seals. Leaks often show at the housing-to-cooler joint. Replacing only one gasket can miss the real weep path.
3. Related coolant flange / hose leaks. Pressure-test so you do not blame the housing when a nearby flange or hose is the real source.

What it usually costs

Housing and gasket parts are moderate; labor adds up in a tight engine bay. Aluminum upgrades cost more.

Is it safe to keep driving?

Do not drive if coolant is critically low or the engine is overheating.

DIY or shop?

Experienced DIY possible; many owners use a BMW/Toyota specialist.

Recalls, bulletins and complaints in plain words

• Related recalls: NHTSA lists these recalls touching this area of the Toyota: 21V598000 (2020-2021 model years, engine); 23V821000 (2023-2023 model years, power train:automatic transmission:control module (tcm/pcm/tecm)); 25V636000 (2020-2022 model years, electrical system:starter assembly:relay); 26V056000 (2021-2023 model years, electrical system:starter assembly). Check your VIN at nhtsa.gov/recalls. If your car is part of a recall, the dealer fixes it for free.
• Plain words: The complaint count below shows how often owners reported problems that mention these words to NHTSA. A count is not proof of a defect.
• NHTSA complaints: 8 keyword-matched complaints for Toyota Supra 2020–2025 (of 47 unique complaints queried, NHTSA complaints API by model year, queried 2026-11-06; keywords: coolant, oil, leak, filter, housing) (NHTSA returned no data for 2 model-year queries). This counts complaints that mention these words. It is not a defect finding.

What owners report

• In Aluminum Oil Filter Housing on Reddit r/Supra, owners discussed upgrading the B58 plastic housing.
• In Sudden failure risk of B58 oil filter housing? on Reddit r/BmwTech, B58 owners debated how badly the plastic housing can fail.
• In B58 OIL FILTER HOUSING HEADACHE on Reddit r/BmwTech, an owner described a difficult housing leak repair.
• In NEED HELP:( on Reddit r/Supra, a Supra owner sought help with a cooling/oil-related issue around the filter housing area.

Quick tip

Same B58 housing story as BMW—catch the seep early so you are not mixing oil and coolant.

Vehicle focus: Toyota GR Supra A90/A91 B58 roughly 2020-2025.

Safety / mechanic note

Overheating or oil/coolant mix can kill the engine. Verify with a mechanic.