Parts for your 2020 Toyota Vitz|yaris-Sump plug washers

2020 Toyota Vitz/Yaris sump plug washers — what they do and when to replace them

Yes, the 2020 Toyota Vitz/Yaris uses a sump plug washer. Toyota’s Technical Information System (TIS) repair manual for Vitz/Yaris models around 2018–2020 (engine lubrication section) specifies installing the drain plug with a new gasket each time the engine oil is changed. The Toyota Electronic Parts Catalogue (EPC) lists the oil drain plug gasket as a separate, replaceable item (commonly Toyota P/N 90430-12031, aluminium crush type) across late Vitz/Yaris variants, including the Japanese Vitz (KSP/NSP/NCP series) and early 2020 Yaris models. Independent data services and workshop guides for these vehicles also call out “fit new washer on refit”. That means the sump plug washer is relevant and fitted to this vehicle.

On the 2020 Vitz/Yaris, the sump plug washer is a small, single-use crush gasket that sits between the oil sump (pan) and the drain plug. When the plug is tightened, the washer deforms slightly to seal the joint. It’s there to prevent weeping or drips after an oil change and to let the plug reach its correct torque without chewing into the alloy pan.

Best practice is to replace the washer at every oil change. It’s a cheap part, and skipping it can lead to annoying leaks or an overtightened plug. Most Toyota small engines of this era specify about 39–40 N·m for the drain plug, always confirm for the exact engine code in the repair manual. If the plug’s been overtightened before, it’s worth inspecting the threads and the sealing face for nicks.

• Use the correct washer: Toyota’s aluminium crush gasket (e.g., 90430-12031) suits the M12 drain plug used on many Vitz/Yaris engines.
• Replace every service: single-use design, don’t reuse a flattened or grooved washer.
• Fit clean and dry: wipe the sump face and plug head, no sealants or thread tape.
• Start the plug by hand, then torque to spec, don’t “double up” washers to chase a seal.
• Watch for tell-tales after a service: dampness around the plug, a drip on the driveway, or oil mist underneath usually points to a tired washer or incorrect torque.

For owners who DIY, keeping a couple of genuine washers on hand makes servicing simple. For workshop jobs, it’s reasonable to expect a fresh washer is part of the oil change consumables.

Popular questions

Does the 2020 Toyota Vitz/Yaris actually have a sump plug washer?
It does. Toyota’s own service literature instructs fitting the drain plug with a new gasket at each oil change, and the parts catalogue lists the washer (commonly 90430-12031) as a separate, replaceable item. If the plug is removed for a service, a new crush washer should go on before refitting.

How often should the washer be replaced, and what torque should be used?
Replace the washer every oil change. Tighten the drain plug to about 39–40 N·m, then check the exact spec for the engine code in the repair manual. Correct torque plus a fresh washer means no leaks and no drama.

Can the old washer be reused to save a few bucks?
Not recommended. The washer is designed to crush once. Reusing it risks seepage or needing extra torque that can damage threads in the alloy sump. A new genuine-style washer is inexpensive and avoids bigger headaches.