Parts for your 2018 Mitsubishi Eclipse cross-Sump plug washers

2018 Mitsubishi Eclipse Cross sump plug washers

Technical documentation confirms the 2018 Mitsubishi Eclipse Cross uses a replaceable sump plug washer (crush washer) on the engine oil drain plug. The Mitsubishi Motors Workshop Manual for Eclipse Cross (GK/GL, 2018–, Lubrication—Engine Oil) specifies replacing the drain plug gasket whenever the plug is removed and tightening the plug to a set torque. The Mitsubishi ASA electronic parts catalogue for Eclipse Cross models lists a “GASKET, OIL DRAIN PLUG” for the sump, commonly an M14 aluminium crush type (widely supplied under Mitsubishi part references such as MD050317 across late-model engines). Major aftermarket catalogues used in AU/NZ service trade also list a matching crush washer for the 1.5T Eclipse Cross. So yes—this vehicle is fitted with, and relies on, a sump plug washer.

On this model, the sump plug washer’s job is simple but critical: it seals the drain plug against the alloy sump to keep engine oil where it belongs. It’s a soft, sacrificial ring—usually aluminium—that compresses once to fill microscopic gaps between the plug flange and the sump face. Because it plastically deforms on tightening, it’s considered a single‑use item. Reusing it can lead to weeping oil, messy undertrays, and potential environmental headaches.

For routine servicing, the washer should be replaced at every oil change. The recommended approach is straightforward: remove the old washer, clean the mating face on the sump and the plug, fit a new crush washer of the correct size, and tighten the plug to the specified torque (around the high‑30s N·m range is typical for Mitsubishi M14 plugs—use the exact spec from the service manual). Over‑tightening is a common mistake, on an aluminium sump that can stretch threads, warp the washer, or make the plug a nightmare to remove next time. Under‑tightening can allow seepage.

Good trade practice on the Eclipse Cross includes:

• Always using a new, correct‑size crush washer each oil change.
• Cleaning both sealing faces—no sealants or tape needed.
• Using a torque wrench, not “feel”, to finish the job.
• Checking for any oil misting at the plug after the first warm run.
• Inspecting the plug flange for nicks or burrs and replacing the plug if damaged.

Whether commuting in Auckland or touring regional Australia, keeping that tiny washer fresh is cheap insurance against leaks and keeps the Eclipse Cross tidy and compliant.

Popular questions

What size sump plug washer does a 2018 Eclipse Cross use?
The Eclipse Cross typically uses an M14 crush washer with an outside diameter around 22–24 mm, as listed in Mitsubishi ASA and common AU/NZ parts catalogues. Workshops often stock the standard Mitsubishi aluminium M14 gasket used across many late‑model engines.

When in doubt, matching by VIN or measuring the existing plug flange diameter ensures the correct fit and proper sealing.

How often should the sump plug washer be replaced?
It’s a one‑and‑done item—replace it every time the drain plug is removed for an oil change. That’s the procedure called out in the Mitsubishi workshop manual and standard trade practice in Australia and New Zealand.

Skipping replacement risks slow weeps that can be mistaken for rear main or sump gasket leaks down the track.

What torque should the drain plug be tightened to?
Mitsubishi specifies a set torque in the Eclipse Cross workshop manual, for M14 plugs it’s typically in the high‑30s N·m. Using a torque wrench protects the alloy sump threads and ensures the new washer crushes correctly.

If the exact figure isn’t on hand, workshops reference the factory manual or reputable data services before buttoning up.