Parts for your 2021 Honda Odyssey-Sump plug washers

2021 Honda Odyssey sump plug washers

Based on Honda’s own technical literature, the 2021 Honda Odyssey does use a sump plug washer (crush washer) on the engine oil drain bolt. The 2021 Odyssey owner’s manual and service information specify refitting the drain bolt with a new washer at each oil change and tightening to the published torque (about 39 N·m/29 lb·ft). Honda parts catalogues list a 14 mm aluminium crush washer (commonly referenced as Honda P/N 94109-14000) for the engine oil drain plug. These manufacturer sources confirm the washer is fitted and is considered a single‑use service item.

For the 2021 Honda Odyssey, the sump plug washer does a deceptively big job. It’s a single‑use, soft aluminium “crush” ring that deforms slightly when the drain bolt is tightened. That controlled crush creates a reliable seal between the sump and the bolt, keeping engine oil where it should be and stopping those annoying drips on the driveway.

Honda expects this washer to be replaced every time the oil is changed. Reusing an old one can lead to tiny weeps that turn into a slow leak, or tempt overtightening of the bolt to make it seal—neither is a good outcome. Overtightening risks damaging the pan threads, under‑tightening risks seepage. Following Honda’s torque spec—about 39 N·m—lets the new washer crush just right without stressing anything.

While it looks generic, it’s worth sticking with the correct 14 mm Honda‑spec washer. The right hardness and thickness matter. Many mechanics keep a small stash on hand, swapping one in as part of routine servicing, right alongside the new oil filter. It’s a cheap part that protects a very expensive engine and saves a lot of mess.

Good practice on the Odyssey is simple:

• Use a new 14 mm aluminium crush washer at every oil change.
• Wipe the sump’s sealing face clean before refitting the bolt.
• Tighten the drain bolt to the specified torque (about 39 N·m).
• Check for seepage after the first heat cycle, if there’s a drip, don’t crank the bolt tighter—replace the washer and re‑torque.

Signs the washer needs attention include a faint oil halo around the plug, a single drip after parking overnight, or evidence the old washer is hard, grooved, or flattened unevenly. Swapping it is quick, inexpensive, and exactly what Honda’s service guidance expects for the 2021 Odyssey.

Popular questions about 2021 Honda Odyssey sump plug washers

What size sump plug washer does the 2021 Odyssey use?
The Odyssey’s engine oil drain bolt uses a 14 mm aluminium crush washer. Honda commonly supplies this as P/N 94109‑14000. It’s designed to be single‑use so it crushes correctly when tightened to about 39 N·m, giving a proper seal without overloading the threads.

Do I really need to replace the washer at every oil change?
Yes. Honda’s service information calls for a new washer each time the drain bolt is refitted. Reusing an old washer can cause slow weeps or encourage over‑tightening to chase a seal. Given the low cost, replacing it each service is the smart move.

What if it still leaks after I replace the washer?
Confirm the torque, make sure the sump face and bolt head are clean and flat, and use a correct Honda‑spec 14 mm washer. If it still weeps, inspect the drain bolt for nicks and the sump threads for damage. Avoid sealants or tape—if threads are compromised, get them repaired properly.