The Importance of the Drain Plug Washer: Everything You Need to Know About Crush Washers

When changing your car’s oil, the focus is often on the filter and oil quality—but there’s another small part that plays a vital role in maintaining engine health: the drain plug washer. Whether it’s a crush washer M12, an aluminum drain plug washer, or a rubber composite, choosing the right type and replacing it regularly is key to a leak-free oil change.

In this article, we’ll explore what these washers do, the different types like the crush washer M14, and how auto parts retailers like Advance Auto Parts can help you find the right fit for your vehicle.

What Is a Drain Plug Washer and Why It Matters

The car drain plug washer—also referred to as an oil drain plug gasket or drain bolt crush washer—sits between the oil drain plug and the oil pan. Its function is simple but crucial: it creates a tight seal to prevent oil leaks after an oil change.

When a drain plug is tightened without a washer, or with a worn washer, the metal-to-metal contact between the bolt and the oil pan may not seal perfectly. This results in slow leaks that can lead to reduced oil levels, oil spots in your driveway, and, in severe cases, engine damage from low lubrication.

Types of Drain Plug Washers:

Crush washers (single-use, soft metal)

Flat washers (reusable, harder material)

Rubber-composite washers (flexible, reusable in some cases)

Of all these, crush washers are the most common and widely recommended for proper sealing.

Crush Washers: M12, M14, and Aluminum Types

A crush washer is designed to deform slightly when you tighten the oil drain bolt. This creates a tight seal against the oil pan surface. These washers are typically made from soft metals like aluminum or copper and are generally intended for one-time use.

Crush Washer M12
A crush washer M12 is designed for a 12mm drain plug. It’s commonly used in various Japanese and Korean vehicles, such as Honda, Hyundai, and Mazda. This washer is ideal for creating a tight seal and should be replaced with every oil change.

Crush Washer M14
The crush washer M14 fits a 14mm oil drain bolt, found in many European and American vehicles. Like its M12 counterpart, it's typically made from soft metals and is a one-use item. Always check your vehicle’s manual or oil pan bolt thread size to ensure compatibility.

Aluminum Drain Plug Washer
The aluminum drain plug washer is a popular choice for crush washers due to its balance of strength and deformability. It’s resistant to corrosion and provides a reliable seal. Aluminum washers are widely available in both M12 and M14 sizes.

Drain Bolt Crush Washer
This is just another name for the same part—it's the washer that goes on the drain bolt (or drain plug). Regardless of terminology, the function remains the same: to provide a leak-proof seal during an oil change.

Where to Find and Replace Your Washer: Advance Auto Parts and More

Replacing a car drain plug washer is simple, affordable, and essential. Yet many vehicle owners either reuse old washers or forget them entirely. If you’re looking for quality replacements, stores like Advance Auto Parts carry a wide selection, including both OEM-style and aftermarket crush washers.

Crush Washer Advance Auto Parts
Advance Auto Parts is a trusted supplier for automotive maintenance components. You can find crush washer M12, crush washer M14, and a variety of aluminum drain plug washer options both online and in-store. These come in packs of 2, 5, or even bulk quantities, so you can stock up for future oil changes.

Tips for Washer Replacement:

Always match the size to your vehicle's specifications (M12, M14, etc.).

Never reuse a crush washer—once compressed, it loses its sealing ability.

Inspect the drain bolt for damage or burrs that could prevent a proper seal.

Torque the drain plug to manufacturer specs—over-tightening can flatten the washer excessively or damage the oil pan.

Replacing the washer is as simple as sliding off the old one and placing the new one onto the drain bolt before tightening. A properly installed washer ensures no leaks and protects your engine.

A good oil change isn’t just about fresh oil—it’s about preventing leaks and protecting your engine from damage. The humble drain plug washer, especially the crush washer M12, crush washer M14, or aluminum drain plug washer, plays an indispensable role in that process.

Whether you buy your crush washer at Advance Auto Parts or stock up from another source, don’t overlook this small but mighty component. Make it a habit to replace your drain bolt crush washer every oil change and ensure your engine stays sealed, lubricated, and leak-free.