What size socket do I need to remove an oil plug?

Typically a 14mm socket fits the oil drain plug on most modern passenger cars, but sizes vary by model. Check your owner's manual or inspect the plug head to confirm, and start with 14mm; if it doesn’t fit, try nearby sizes instead of forcing it.

Common drain plug sizes you’re likely to encounter

Knowing the usual sizes helps you prepare before you begin. The list below covers the most common possibilities across a wide range of vehicles.

• 14mm: The prevailing metric size for many contemporary cars (Toyota, Honda, GM, Ford, VW, etc.).


• 12mm or 13mm: Less common, but found on some European makes and older models.


• 17mm or 19mm: Occasionally used on certain trucks, SUVs, or specialty vehicles.

Using the correct socket prevents rounding the head and reduces the risk of leaks when re-tightening.

How to verify and prepare your socket

To confirm you have the right size and to avoid damage, follow these steps. Note that some plugs use non-standard heads requiring different tools.

1. Check the owner's manual or service guide for the exact drain plug size and head type for your vehicle.


2. Inspect the plug head. If it has a straight external hex, start with a 14mm (or the closest metric size). If the head is an internal hex (Allen), use the corresponding Allen key size (commonly 6mm or 8mm). If the head is Torx or another style, use the matching bit.


3. Gently test-fit the socket. It should seat snugly and turn without slipping. If it feels loose, try the next size up or down.


4. When reinstalling, tighten to the manufacturer’s specification using a torque wrench to avoid leaks or damage.

Choosing the wrong size can strip the plug or pan, so take a moment to verify before applying full force.

Alternate head types you might encounter

Some vehicles use non-standard drain plug heads. If your plug head isn’t a typical external hex, you may need an Allen key (internal hex), a Torx bit, or a specialty driver. Verify with the manual or by inspecting the plug before buying tools.

When in doubt, consider a quick visit to a local shop or mechanic for a quick check. Proper tool selection saves time and reduces risk of damage.

Summary

In short, a 14mm socket fits many oil drain plugs, but not all. Sizes vary by vehicle, and some plugs use alternative head types. Always verify with the owner’s manual or by inspecting the plug, and use the appropriate tool to avoid damage or leaks during an oil change.

What size socket to remove oil drain plug?

The correct socket size for an oil plug depends on your car's make and model, as there is no single universal size. Common metric sizes include 14mm, 15mm, 17mm, and 19mm, while some older vehicles may use SAE sizes like 3/8" or 1/2". Always inspect the plug to confirm the size, as using the wrong socket can damage the bolt head. 
You can watch this video to learn how to change the oil in a Honda CR-V, including removing the drain plug: 1m1A Auto: Repair Tips & Secrets Only Mechanics KnowYouTube · Aug 13, 2018
How to find the right size

• Check your owner's manual: This is the most reliable way to find the correct size for your specific vehicle. 
• Inspect the plug: Visually examine the drain plug to determine its size. You can also measure it with a caliper if needed. 
• Try common sizes: If you can't find your manual, start with common metric sizes like 14mm, 15mm, 17mm, or 19mm. 
• Use the right socket type: A 6-point socket is recommended over a 12-point socket to prevent stripping the bolt head. 

This video demonstrates how to use a drain plug removal tool with a magnetic feature: 52sScavenger1320YouTube · Feb 23, 2024
Important tips

• Use the correct socket: A well-fitting socket is crucial to avoid rounding the bolt head. 
• Tighten properly: Do not overtighten the drain plug, as this can strip the threads. Tighten it to the manufacturer's specifications, or just snug it up if you don't have a torque wrench. 
• Replace the crush washer: It is a good practice to replace the crush washer on the drain plug to ensure a proper seal. 

What size is the most common oil plug?

Most cars use oil drain plugs between 13mm and 17mm, depending on the brand.

How to loosen a tight oil drain plug?

To loosen a tight oil drain plug, first use a 6-point socket and a long breaker bar or a pipe extension to get more leverage. Next, apply a penetrating oil and tap the plug or wrench with a hammer to help break it free. If it's still stuck, apply heat to the plug head to expand it before trying to turn it again.
 
Step 1: Apply penetrating oil and tap 

• Spray the drain plug with a penetrating oil like PB Blaster or Liquid Wrench and let it soak in. 
• Tap the head of the plug or the end of the wrench handle with a hammer to help the oil penetrate and break the bond. 

This video demonstrates how to use penetrating oil and a hammer to loosen a stuck oil drain plug: 1mHow That Works - With Hank BaughYouTube · Apr 16, 2023
Step 2: Use leverage and force 

• Use a 6-point socket, as it provides a better grip and is less likely to round off the plug than a 12-point socket. 
• A breaker bar is ideal for the job due to its long handle, which provides significant leverage. 
• If you don't have a breaker bar, slide a pipe over the end of a standard ratchet to extend its length and increase leverage. 
• Apply steady, firm pressure to turn the plug counterclockwise to loosen it. 

You can watch this video to see how to use leverage and force to loosen an oil drain plug: 50sDom BYouTube · Nov 28, 2018
Step 3: Apply heat 

• If the plug is still stuck, use a heat gun or lamp to warm the area around the plug. 
• Heat the plug head directly, not the surrounding oil pan, to make the plug expand more than the pan. 
• After heating, use your breaker bar or extension to try loosening the plug again. 

This video shows how to apply heat to a stuck oil drain plug: 1mRastaman BuildsYouTube · Mar 3, 2023
Step 4: Use alternative methods (if needed)

• If the plug's head is stripped or rounded, use a specialized extractor socket that bites into the bolt. 
• Alternatively, you can use a vise-grip to clamp onto the plug, or as a last resort, use a drill to make a hole in the center to use an extractor set. 
• As a final option, you could also try welding a nut to the plug, which gives you a new surface to turn with a wrench. 

You can watch this video to learn how to remove a stripped oil drain plug using an extractor socket: 55sGearHeads with FinallyHeSleepsYouTube · Dec 16, 2022

What size is the oil drain plug bolt?

There is no universal size for an oil drain plug, but common sizes for passenger cars include 15mm and 17mm. Other sizes like 13mm, 14mm, or inch-based sizes (9/16"9 / 16 "9/16") can also be used depending on the vehicle's make and model. To be certain, check your owner's manual or use a wrench that fits your specific plug snugly. 
Common sizes and how to find the right one

• Metric: Common metric sizes include 13mm, 14mm, 15mm, and 17mm. For example, an M12x1.75 plug may use a 14mm or 15mm wrench, and some models might even use a 10mm head on a larger bolt, so it's best to verify. 
• Imperial: Some vehicles, particularly older American models, use imperial sizes such as 3/8"3 / 8 "3/8" or 1/2"1 / 2 "1/2". 
• How to determine the correct size: The most accurate way is to consult your vehicle's owner's manual. If that's not an option, the best approach is to try a few common sizes to see which one fits. 
• Why a correct fit is important: Using a wrench that is too small can round off the bolt head, making it difficult to remove. A snug fit is essential to avoid damage.