What Is a Crush Washer and When to Replace It
A crush washer is a soft metal ring that seals the oil drain plug, and the assortments in this guide span M5 to M24.
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maierke 1160PCS Crush Washer Oil Drain Plug,189.7/10View on Amazon - 2
maierke 360PCS Crush Washer Oil Drain Plug,189.6/10View on Amazon - 3
330 Pcs Copper Washers Assortment Kit9.5/10View on Amazon - 4
Seamaka Oil Crush Washer,18 Sizes Oil Drain Plug9.5/10View on Amazon
The oil is drained, the plug is back in, and a slow drip is forming under the pan by morning. What is a crush washer is the question behind that drip: a soft metal ring that sits under the drain plug and seals it, and the assortments in this guide span M5 to M24.
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maierke 1160PCS Crush Washer Oil Drain Plug,18
A 1160 piece copper and aluminum crush washer assortment in 18 sizes from M6 to M24, in a labeled portable box.
Pros
- 1160 pieces: 489 copper and 671 aluminum washers
- 18 sizes from M6 to M24 in both metals
- Labeled portable plastic box for fast picks
- Copper and aluminum stated corrosion and oxidation resistant
Cons
- No warranty term is stated
- No stated weight per washer
- Two metals in one box means sorting by material too
maierke 360PCS Crush Washer Oil Drain Plug,18
A 360 piece copper crush washer assortment in 18 sizes from M6 to M24, in a labeled plastic box.
Pros
- 360 copper washers in 18 sizes from M6 to M24
- Copper stated corrosion and oxidation resistant
- Labeled plastic box for fast picks
- Seals better than a rubber gasket, per the listing
Cons
- No warranty term is stated
- Copper only, no aluminum washers
- No stated weight per washer
330 Pcs Copper Washers Assortment Kit
A 330 piece copper washer assortment, 12 sizes stated and 8 named from M5 to M20, in a clear plastic box, for oil drain plugs, sump plugs and fuel fittings.
Pros
- 330 copper washers, 0.5 pounds in total
- Clear plastic box keeps sizes visible and tidy
- Stated for sump plugs, fuel fittings and hydraulic systems
- Size range starts at M5, smaller than the other kits
Cons
- No warranty term is stated
- No aluminum washers included
- No stated label per size in the box
Seamaka Oil Crush Washer,18 Sizes Oil Drain Plug
A 510 piece aluminum crush washer assortment in 18 sizes from M6 to M24, in a transparent storage box with a label.
Pros
- 510 aluminum washers in 18 sizes from M6 to M24
- Aluminum stated corrosion and oxidation resistant
- Transparent storage box with a label per size
- Stated for oil pipes, hydraulic fittings and oil drainage
Cons
- No warranty term is stated
- Bullets list sizes only up to M20 while the title states M6 to M24
- Aluminum only, no copper washers
what is a crush washer: a ring that seals the drain plug
A crush washer sits between the oil drain plug and the oil pan. The listings state it reduces friction between fasteners, disperses pressure and prevents leakage and looseness. Copper and aluminum are the soft metals in these kits, and the listings state they are corrosion-resistant and oxidation-resistant. The maierke and Magicave listings state the seal is better than a rubber gasket. For the rest of the job, see our oil drain pan guide and the oil filter wrench guide.
Match the size to the plug
Each kit lists its sizes in metric. The maierke kits and the Seamaka kit list 18 sizes from M6 to M24, while the Magicave kit (on Amazon) lists 12 sizes from M5 to M20. Check the drain plug size before ordering, and pick the washer that matches it. The maierke kits use a plastic box with a label for each model, and the Seamaka kit a transparent storage box with a label. The Magicave kit comes in a clear plastic box, with no label stated.
When to replace a crush washer
The listings do not state when to replace a crush washer. What they do state is the job it does: sealing the drain plug against leaks. Keep a spare in the box: the assortments here hold from 330 to 1160 washers in the sizes listed above. For the plug itself, see our oil pan drain plug size guide.
Crush washer assortments for the oil change
The sizes above need the right washer in hand, and the 4 kits below cover them from a 360 piece copper set to an 1160 piece mixed-metal assortment.
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FAQ: garage tools
What is a crush washer?
A soft metal ring, copper or aluminum, that sits between the oil drain plug and the oil pan and seals the joint. The listings state it reduces friction between fasteners, disperses pressure and prevents leakage and looseness.
What sizes do crush washers come in?
The maierke and Seamaka kits list 18 sizes from M6 to M24, and the Magicave kit lists 12 sizes from M5 to M20.
Copper or aluminum: which one?
The 360 piece maierke kit is copper, the Seamaka kit is aluminum, and the 1160 piece maierke kit mixes 489 copper and 671 aluminum washers. The listings state both metals are corrosion-resistant and oxidation-resistant.
How do I find the right size in the box?
The maierke kits use a plastic box with a label for each model, and the Seamaka kit a transparent storage box with a label. The Magicave kit comes in a clear plastic box, with no label stated.
Can I use a crush washer on other fittings?
The listings state these washers are also used on oil pipes, hydraulic joints, fuel fittings and sump plugs. Match the size to the fitting.
Related: the engine and shop equipment hub, the how to change oil guide and the crush washer kit for oil changes guide.
