Parts for your 2003 Honda Odyssey-Sump plug washers

2003 Honda Odyssey sump plug washers – what they do and when to replace them

Yes, the 2003 Honda Odyssey does use a sump plug washer on the engine oil drain plug. Honda’s own technical literature — the 2003 Odyssey Owner’s Manual (Engine Oil and Filter section), the Honda Service Manual for the RA6/RA7 platform, and the Honda parts catalogue — all specify fitting a new crush-type drain plug washer whenever the engine oil is changed. The common Honda part for the engine oil drain is a 14 mm aluminium crush washer (Honda P/N 94109-14000). For anyone also servicing the automatic transmission, its drain plug uses a separate sealing washer (often noted as Honda P/N 90471-PX4-000).

On this Odyssey, the sump plug washer is a simple, single-use sealing ring that deforms slightly as the drain plug is torqued down. That controlled “crush” fills tiny imperfections between the plug and the sump, creating a reliable seal that prevents weeping and drips. Because the washer permanently compresses, reusing it is a false economy — it won’t crush the same way twice and can leave the van with an annoying oil spot on the driveway.

Best practice for Aussie and Kiwi owners is to replace the washer at every oil change. It’s a low-cost part that protects the sump threads, keeps the plug torque consistent, and helps avoid leaks down the track. The Service Manual also calls out the correct tightening: torque the engine oil drain plug to 39 N·m (29 lb·ft). Nipping it up harder doesn’t make it seal better — it risks stripping threads or crushing the washer unevenly.

Handy tips for a tidy job:

• Use a fresh 14 mm aluminium crush washer on the engine oil drain plug every service.
• Wipe the mating surfaces clean before refitting.
• Tighten with a torque wrench to 39 N·m. No rattle gun needed.
• If you’re also draining ATF, have the correct transmission drain washer on hand — it’s a different size to the engine one.

If there’s any oil dampness around the plug after an oil change, the usual culprits are a reused washer, dirt on the sealing face, or over/under-tightening. A new washer and correct torque almost always sorts it. It’s a tiny part that does a big job keeping the Odyssey tidy and leak-free.

Popular questions about 2003 Honda Odyssey sump plug washers

What size sump plug washer does the 2003 Odyssey use?
For the engine oil drain, it takes a 14 mm aluminium crush washer (Honda P/N 94109-14000). If you’re servicing the automatic transmission as well, that drain plug uses a different, larger sealing washer (often listed as Honda P/N 90471-PX4-000).

How often should the sump plug washer be replaced?
Every oil change. The washer is designed to crush once and provide a fresh seal each time. Reusing it can lead to weeping, inconsistent torque, and potential thread damage from over-tightening to chase a seal.

What’s the torque spec for the engine sump plug?
Tighten the engine oil drain plug to 39 N·m (29 lb·ft). Using the correct torque with a new crush washer is the best recipe for a clean, leak-free seal without stressing the threads in the alloy sump.