Parts for your 2020 Mitsubishi Eclipse cross-Sump plug washers

2020 Mitsubishi Eclipse Cross sump-plug-washers

Based on Mitsubishi technical sources — namely the Mitsubishi Motors Workshop Manual for the Eclipse Cross (4B40 engine, Engine Lubrication section) and Mitsubishi ASA/parts catalogue entries — the 2020 Mitsubishi Eclipse Cross uses a crush-type sump plug washer (drain plug gasket). The manual specifies refitting the drain plug with a new aluminium washer whenever the plug is removed for an engine oil change.

On this model, the sump plug washer’s job is dead simple but critical: it crushes slightly as the plug is torqued up, creating a gas- and oil-tight seal between the sump and the plug. That soft aluminium ring takes up tiny imperfections in the mating faces, so the plug can be correctly tightened without relying on brute force to stop leaks. It’s a small, inexpensive consumable that protects against drips, stripped threads and comeback issues after servicing.

For owners and workshops servicing a 2020 Eclipse Cross, the best practice is to replace the sump-plug-washer at every engine oil change. Mitsubishi’s documentation calls for a new washer on refit, and that’s because once a crush washer has been compressed, it won’t reliably reseal a second time. Reusing it can lead to weeping around the plug, oil on the driveway, and a mess under the car. A fresh, correct-size aluminium washer (commonly M14 on this engine) restores the proper sealing each time.

When fitting the new washer, clean the plug and sump face, then tighten the plug to the specified torque listed in the workshop manual for the 4B40 engine. Avoid over-tightening — it won’t improve sealing, but it can distort the washer, damage threads, or even crack the sump. If the exact torque isn’t at hand, use a torque wrench and follow Mitsubishi’s spec from the service literature.

• Replace the washer at every oil change or any time the drain plug is removed.
• Use a quality aluminium crush washer in the correct size for the Eclipse Cross sump plug.
• Inspect after the first short drive: if there’s any dampness around the plug, recheck torque and the washer’s seating.

Signs the washer needs attention include a faint oil ring on the sump around the plug, spots under the vehicle after parking, or a plug that feels “soft” before reaching torque. Keeping on top of this little part keeps the 2020 Mitsubishi Eclipse Cross tidy, leak-free and easy to live with across Aussie and Kiwi conditions.

Popular questions about 2020 Mitsubishi Eclipse Cross sump-plug-washers

What size washer does the Eclipse Cross use?
The 2020 Eclipse Cross typically uses an M14 aluminium crush washer on the engine oil drain plug, as referenced in Mitsubishi parts catalogues for the 4B40 engine. Always match by vehicle VIN or measure the plug to confirm before servicing.

How often should the sump plug washer be replaced?
Every time the drain plug is removed — practically, that’s every engine oil change. Mitsubishi’s service information calls for a new washer on refit to guarantee a proper seal and prevent seepage.

Can a sump plug washer be reused if it looks okay?
It’s not recommended. Crush washers are designed to deform once. Reusing one can lead to minor leaks or require over-tightening, which risks thread damage. A new washer is cheap insurance at each service.