Parts for your 2016 Mitsubishi Lancer-Sump plug washers

2016 Mitsubishi Lancer sump plug washers — what they do and when to replace them

Technical sources for the 2016 Mitsubishi Lancer confirm a sump plug washer is fitted and required. The Mitsubishi Motors service manual for 4B11/4B12 engines (Engine Lubrication section) instructs to “replace the drain plug gasket” during an oil change, and the Mitsubishi ASA parts catalogue lists a 14 mm crush washer (gasket) under part number MD050317 for the engine oil drain plug (common drain plug PN MN132895). That makes sump plug washers absolutely relevant to any 2016 Lancer oil service.

The sump plug washer is a small, single-use crush ring that seals the gap between the drain plug head and the sump. When tightened to spec, it deforms slightly to create a fluid-tight seal that resists heat cycles, vibration and pressure variations. Without a good washer, even a correctly torqued plug can seep, leaving tell-tale oil mist on the sump or a drip on the driveway.

On the 2016 Lancer, the washer is a 14 mm internal diameter crush type, typically copper or aluminium. Either material is fine so long as it matches the correct size and spec, genuine MD050317 is the safe bet. The washer also helps protect the alloy sump by achieving the seal at lower torque than a bare metal-to-metal interface, reducing the risk of stripped threads from “gorilla-tight” spanner work.

Best practice is to replace the washer at every oil and filter change. It’s inexpensive insurance against leaks. After draining the oil, clean the sump’s sealing face, fit a fresh washer to the plug, and torque the plug to the factory spec of 39 N·m (about 29 ft·lb). Don’t add sealant—if a sealant seems necessary, the washer is wrong or the mating faces need attention.

A quick visual once-over after the first short drive helps, too. Any wetness around the plug suggests the washer wasn’t seated, the torque is off, or the wrong size was used. For vehicles running aftermarket magnetic plugs, a crush washer is still required—magnet or not, the seal comes from the washer.

• Replace the washer every service interval (typically each oil change).
• Use the correct 14 mm ID crush washer (e.g., MD050317), avoid generic “close enough” sizes.
• Tighten to 39 N·m, don’t overtighten.
• Inspect for weeps after the first heat cycle.

Popular questions about 2016 Mitsubishi Lancer sump plug washers

What size sump plug washer does a 2016 Lancer use?
Most 2016 Lancer petrol models (4B11/4B12) use a 14 mm internal diameter crush washer. The genuine Mitsubishi gasket is commonly listed as MD050317. Always confirm by VIN if the vehicle has a different engine or replacement sump/plug.

How often should the sump plug washer be replaced?
Replace it every oil change. The washer is designed to crush once, reusing it risks slow leaks and can throw off the required torque. Given the low cost, a new washer each service is the smart move.

Copper vs aluminium—does it matter?
Both work well when they’re the correct size. Copper crush washers deform smoothly and handle heat well, aluminium is equally common and seals reliably. Stick with quality parts, and don’t rely on re-annealing or reusing—single use is the manufacturer’s intent.