Parts for your 2005 Toyota Highlander-Sump plug washers

2005 Toyota Highlander (Kluger): Sump Plug Washers — What They Do and When to Replace

According to Toyota’s factory service guidance and the Toyota Electronic Parts Catalogue, the 2005 Toyota Highlander (sold as Kluger in Australia and New Zealand) uses a replaceable sump plug washer (also called an oil drain plug gasket). For the 2.4L 2AZ-FE and 3.3L 3MZ-FE engines fitted to this model year, Toyota specifies a crush-type aluminium washer commonly listed as P/N 90430-12031 for an M12 drain plug. Parts can vary by market and VIN, but the technical documentation is clear that a washer is fitted and intended to be replaced as needed.

This little washer does big work. It sits between the sump (oil pan) and the drain plug, deforming slightly when tightened to create a tight, leak-free seal. Because it’s a crush design, it’s made to be used once, reusing it can lead to weeping around the plug, drips on the driveway, or a plug that needs over-tightening to seal properly.

Best practice for a 2005 Highlander/Kluger oil service is to inspect and replace the sump plug washer at each oil change. They’re inexpensive insurance against leaks, and swapping one takes seconds while the oil is draining. When refitting the plug with a fresh washer, tighten to the Toyota spec of around 39 N·m (about 29 ft‑lb). That torque is enough to properly crush the washer and seal without risking damage to the threads in the alloy sump.

Owners who do their own servicing should keep a few spare washers on hand. Look for an M12 crush washer in aluminium (Toyota’s usual spec), copper crush washers can work in a pinch but may feel firmer and can require a touch more effort to seal. If the old washer looks deeply grooved, flattened, or stuck to the pan, replace it—don’t stack washers or reuse a distorted one.

Signs it’s time to pay attention include a faint oil smear radiating from the plug after a change, a drip forming overnight, or a plug that suddenly feels like it needs “just a bit more” to stop weeping. Rather than leaning on the spanner and risking a stripped pan, fit a new washer and torque it correctly. That simple step keeps the Highlander/Kluger tidy underneath and helps maintain proper oil level between services.

• Use the correct-size crush washer (typically M12, aluminium).
• Replace at each oil change or any time the plug is removed.
• Tighten the drain plug to ~39 N·m, don’t over-tighten.

What size is the sump plug washer on a 2005 Toyota Highlander/Kluger?

It’s typically an M12 crush washer in aluminium. Toyota commonly lists P/N 90430-12031 for this model year and its 2AZ-FE and 3MZ-FE engines. Always confirm by VIN, as regional parts listings can vary.

Do you really need to replace the washer at every oil change?

Yes, that’s the recommendation. The washer is designed to crush once. Reusing it can cause small leaks or force you to over-tighten the plug, which risks damaging the sump threads—far costlier than a new washer.

What’s the correct torque for the drain plug on a 2005 Highlander/Kluger?

Around 39 N·m (about 29 ft‑lb) is the Toyota spec commonly cited for these engines. That’s enough to crush the washer and seal properly without stressing the sump. If a leak appears at spec torque, fit a new washer rather than cranking harder.