Best Crush Washer Kit for Oil Changes (2026): 5 Picks

Compared on paper

Specifications are manufacturer rated, as published on each listing and collected 28 October 2026. Where a listing states a figure two ways, the table shows both.

How the points were given

Each kit is scored on performance, build, value, safety and warranty, using only what the listing publishes. No listing here states a safety listing or a warranty term, so those two scores sit at zero across the board.

Scores run from 9.2 to 9.8: each product’s point total is placed on that range, so more points always means a higher score. Safety counts only for powered gear or where the listing states safety features; where it does not apply, the score is taken over the remaining 90 points.

What the listings tell you

Five kits cover the drain plug drawer: three aluminum kits in the M6 to M24 range, one copper kit in M5 to M14, and one mixed aluminum and copper kit picked by vehicle make. Three titles claim 18 sizes while the size lists that follow name fewer, so count the sizes in the list rather than trusting the headline. No kit here states a warranty term, and none states a safety listing.

Buying guide: the best crush washer kit for oil changes

What is a crush washer

A crush washer is a soft metal washer that deforms under the drain plug to seal the joint. The Magicave listing describes sealing through controlled plastic deformation, which absorbs vibration and resists pressure changes. Because the seal comes from deformation, a washer seals best the first time it is crushed, so a fresh washer gives a fresh seal.

Match the size to the drain plug

Drain plugs take metric sizes from M6 to M24 across these kits, with the copper kit covering M5 to M14. The KOOPATZ kit skips sizes entirely and picks by vehicle make instead, with OEM numbers for Toyota, Honda, Subaru, VW, Audi and Mercedes Benz. Check the plug size or the make before ordering, since a washer that does not match the plug cannot seal.

Copper or aluminum

Copper resists heat and corrosion per the AKOSN listing, which names red copper for heat resistance and corrosion resistance. Aluminum dominates the bigger kits: three aluminum kits offer 570 to 720 pieces across the M6 to M24 range. The KOOPATZ kit mixes both metals. For a home garage doing oil changes, aluminum covers the range; copper suits the smaller metric sizes it lists.

Storage that keeps sizes straight

A kit is only useful if the right size comes out first try. The Nuepuxo box is partitioned and sealed with each size labeled, the Magicave box has labeled compartments, and the AKOSN box is transparent with a size chart. The MUFFINMAN box is a handy storage box without labeled compartments named. Keep the box closed between jobs so sizes do not mix.

Garage Fit Check

• Check the drain plug size before ordering: these kits span M5 to M24, and the KOOPATZ kit picks by make instead.
• Keep the box on the shelf by the oil change gear so the right size is at hand at drain time.
• Count the sizes in the list, not the headline: three titles claim 18 sizes while the lists name fewer.
• Copper and aluminum both seal by deforming, so keep fresh washers in stock for each oil change.

FAQ: garage tools

What is a crush washer?

A soft metal washer that seals by deforming under a drain plug or bolt. The Magicave listing describes sealing through controlled plastic deformation, which absorbs vibration and resists pressure changes to keep fluid from leaking.

How do you use a crush washer on an oil drain plug?

Seat the washer on the drain plug so it sits between the plug and the pan, then tighten: the washer deforms to seal the joint. The listings describe the seal as controlled deformation that prevents fluid leaks, so the washer must match the plug size.

What size crush washer fits an oil drain plug?

It depends on the plug. These kits cover M5 to M24 across the range, with the copper kit covering M5 to M14. The KOOPATZ kit picks by vehicle make instead, with OEM numbers for Toyota, Honda, Subaru, VW, Audi and Mercedes Benz. Match the washer to the plug size or the make.

Do I need a crush washer for an oil change?

Yes, if the drain plug uses one: the washer is what seals the plug against the pan, and the kits here are sold for oil drain plug repair. A flattened washer from the last change may not seal again, so a fresh washer is the standard pick.

Copper or aluminum crush washer?

Both seal by deforming. Copper, per the AKOSN listing, brings heat resistance and corrosion resistance in M5 to M14. Aluminum covers M6 to M24 in the bigger kits, with 570 to 720 pieces. Pick copper for the smaller metric sizes it lists, aluminum for the full range.

Related: best oil drain pan, best oil drain valve, best car ramps for oil changes, and best creeper for oil changes. Also see best floor jack for oil changes and the engine and shop equipment hub.