Parts for your 2012 Subaru Tribeca-Sump plug washers

2012 Subaru Tribeca sump plug washers

A sump plug washer is absolutely used on the 2012 Subaru Tribeca. Technical references including the Subaru Owner’s Manual for the model year (Engine Oil section), the factory Service Manual (Lubrication/Engine Oil) and the Subaru Genuine Parts Catalogue specify a crush-type drain plug gasket fitted to the EZ36 3.6‑litre flat‑six. Subaru’s commonly listed OEM drain plug gasket for this application is the 16 mm aluminium crush washer (Subaru part number 803916010), intended to be replaced at every oil change.

On this Tribeca, the sump plug washer’s whole job is to seal the drain plug to the alloy sump so engine oil doesn’t weep once the plug is torqued. It’s a single‑use, soft metal ring that deforms (“crushes”) when tightened, filling microscopic gaps between the plug’s flange and the sump face. That controlled crush gives a reliable seal without having to overtighten the plug, which helps protect the sump threads and keeps the mating face in good nick.

As part of routine servicing, the washer should be swapped out every time the engine oil is changed. Reusing an old, already‑crushed washer can lead to slow leaks, staining under the car, and the temptation to lean harder on the spanner. Instead, fit a fresh washer, clean both mating surfaces, and tighten the plug to the factory torque spec noted in the service literature. After refilling, a quick look under the bonnet and under the vehicle for the first few drives is a good shout—any drips will show up quickly and can be sorted before they become a headache.

Quality matters here. An OEM Subaru washer—or a reputable equivalent matching the correct 16 mm size and profile—will crush consistently and seal first go. Aluminium is what Subaru specifies for the EZ36, copper washers can work in some scenarios, but the right material, thickness and inner diameter are key to proper crush and torque feel. If the sump face has nicks or old gasket material, dress it lightly and clean it before reassembly. Paired with the right oil and filter, a new washer each service is simple, inexpensive insurance for a tidy, leak‑free Tribeca.

• Replace the washer at every oil change, don’t reuse.
• Clean the plug and sump face before fitting the new washer.
• Tighten to the factory torque spec from the service manual—avoid overtightening.
• Check for weeps after the first heat cycle and short drive.

Popular questions about 2012 Subaru Tribeca sump plug washers

What size washer does the 2012 Tribeca use?
It uses a 16 mm aluminium crush washer on the engine oil drain plug, as listed in Subaru’s parts catalogue for the EZ36 engine. The commonly referenced OEM part is Subaru 803916010. Using the correct size ensures proper crush and sealing without over‑torquing the plug.

How often should the sump plug washer be replaced?
Every oil change. Subaru’s service guidance calls for a new drain plug gasket whenever the plug is removed. It’s a single‑use item—the fresh washer crushes to form the seal, and reusing an old one risks leaks and damaged threads from overtightening.

Can a copper washer be used instead of aluminium?
If it precisely matches the Subaru dimensions and profile, a quality copper crush washer can seal—but Subaru specifies aluminium for this engine. For best results and the right torque feel, stick with the OEM‑style aluminium washer or a direct‑equivalent aftermarket part.