Parts for your 2007 Mitsubishi Lancer-Sump plug washers

2007 Mitsubishi Lancer sump-plug-washers: do you need one and when to replace it?

Based on Mitsubishi technical sources — namely the CH/CJ Lancer workshop manuals and the Mitsubishi ASA parts catalogue — the 2007 Mitsubishi Lancer does use a separate sump plug washer (drain plug gasket). For CH-series engines (like 4G94/4G69) and early CJ (4B11) launched in late 2007, the parts listings specify a single‑use aluminium crush washer for the M14×1.5 drain plug. A commonly cited genuine part is MD050317 (14 mm ID), and the workshop procedures call for refitting with a new washer and tightening the plug to the specified torque (typically around 30–39 N·m, depending on engine variant).

The sump-plug-washer on a 2007 Lancer does a deceptively important job. It’s a soft, crushable gasket that deforms as the drain plug is tightened, filling tiny imperfections between the plug flange and the sump face. That controlled “crush” makes a reliable seal, stops annoying drips on the driveway, and saves the sump threads from copping more torque than they need.

For routine servicing, it’s good practice to replace the washer at every oil change. They’re designed as single-use items, once crushed, they don’t spring back. Reusing can lead to weeping around the plug, especially as the washer hardens with heat cycles. A fresh aluminium or copper washer costs next to nothing and helps keep the sump bone dry. If the car has an aftermarket magnetic plug or a plug with a bonded seal, check the instructions — some of those have captive seals and don’t take a separate washer — but the factory Lancer plug is set up for a crush washer.

• Typical torque: 30 N·m for 4B11 CJ, up to about 39 N·m for CH 4G engines — always verify for the exact engine code.
• Washer size: 14 mm ID for the M14 drain plug (genuine washer commonly listed as MD050317).
• Tools: 17 mm socket is typical for the plug head, plus a torque wrench for accuracy.

When changing oil, clean the mating face on the sump, slip the new washer onto the plug, hand-thread the plug to avoid cross-threading, then torque it properly. Don’t stack old washers, don’t use thread tape, and don’t “swing off” the ratchet — over-tightening can distort the washer and risk damaging threads. After the first heat cycle, have a peek under the bonnet and check for any misting or a tell-tale droplet around the plug. If it’s dry, you’re golden. If there’s a weep, the usual culprits are a reused washer, dirt on the sealing face, or the plug not torqued evenly.

A tiny part, sure — but keeping a fresh sump-plug-washer in the service kit helps your Lancer stay tidy, leak-free, and easy to maintain for the long haul.

Popular questions

What size sump plug washer does a 2007 Mitsubishi Lancer use?
For factory setups it’s a 14 mm internal diameter crush washer for the M14×1.5 drain plug. Mitsubishi parts catalogues commonly list MD050317 as the genuine gasket for CH-era and early CJ Lancers. If the car has had the sump or plug changed, measure the plug or check by VIN to be certain.

How tight should the sump plug be on a 2007 Lancer?
Workshop data typically specifies around 30 N·m for the 4B11 and up to about 39 N·m for CH 4G engines. Using a torque wrench is the go — it seals the new washer properly without over-crushing it or stressing the threads.

Do I need to replace the washer at every oil change?
Yes. The washer is single-use by design. Swapping it at each oil service is cheap insurance against leaks. If you’re using an aftermarket plug with a bonded seal, follow the manufacturer’s guidance, but the stock Lancer plug expects a new crush washer every time.