What Size Socket Do You Need for an Oil Pan?

You won’t find a single universal size. For most cars, the oil drain plug takes a 13–17 mm socket—14 mm and 15 mm are especially common—while some use 19 mm or an internal hex (often 6 mm or 8 mm). If you’re removing the oil pan itself, the perimeter bolts are typically 10 mm heads (M6 bolts), with some vehicles using 13 mm (M8) or, on certain European models, external Torx (E10/E12). Always verify for your specific vehicle.

Clarifying the Task: Drain Plug vs. Oil Pan Bolts

“Oil pan” jobs usually mean one of two things: loosening the drain plug to change oil, or removing the entire oil pan to service gaskets, pickups, or internal components. These tasks use different fasteners and often different socket sizes. Knowing which you’re doing will point you to the right socket and torque specs.

Common Oil Drain Plug Socket Sizes

Most oil drain plugs use a standard hex head or a recessed hex (Allen). The following sizes cover the vast majority of passenger vehicles, SUVs, and light trucks.

• 14 mm: Very common on many Japanese makes (Toyota, Subaru, Mazda) and some Hyundais/Kias.
• 15 mm: Common on many GM and Ford vehicles.
• 13 mm: Seen on various European and Ford models.
• 17 mm: Found on several Hondas/Acuras and some older imports.
• 19 mm: Less common but used on some European models and trucks.
• Internal hex (Allen): Often 6 mm or 8 mm on some VW/Audi, BMW, and select European applications.
• SAE equivalents: 1/2″ or 9/16″ can appear on older or domestic trucks if not metric.

While there are exceptions, having 13–19 mm sockets (plus 6 mm and 8 mm hex bits) will handle most drain plugs you’ll encounter.

Common Oil Pan Bolt Head Sizes (If Removing the Pan)

Oil pan perimeter bolts are smaller and more numerous. They typically secure the pan to the block or lower cradle and require light torque.

• 10 mm hex head (M6 bolts): The most common size across many makes and models.
• 13 mm hex head (M8 bolts): Used on some trucks and larger engines.
• 8 mm hex head: Occasionally used on smaller fasteners or brackets attached to the pan.
• External Torx (E10/E12): Found on some European engines (e.g., BMW and certain Mercedes applications).

Expect mostly 10 mm for the pan bolts, but be ready for 13 mm or external Torx on specific European designs and larger engines.

How to Identify the Correct Socket Size Quickly

If you don’t know the exact size for your vehicle, a quick check can prevent rounding fasteners or delays.

1. Consult the owner’s manual or a reliable service database for your exact year, make, and model.
2. Visually inspect the fastener: is it a standard hex, internal hex (Allen), or external Torx?
3. Measure across the flats with a caliper or use a sizing gauge if available.
4. Test-fit progressively: start with likely sizes (14 mm or 15 mm for drain plugs; 10 mm for pan bolts).
5. Use 6-point sockets for stubborn drain plugs to reduce the risk of rounding.
6. Avoid adjustable wrenches; they can slip and damage the fastener.

These steps help you land the correct tool fast and protect the fastener from damage, especially on older or corroded plugs.

Torque and Best Practices

Proper torque prevents leaks and stripped threads. Typical passenger-car drain plug torque is about 25–35 ft-lb (34–47 N·m), but always use the spec for your vehicle—some are lower or higher. Replace the crush washer or gasket if your design uses one (common on many Japanese makes). Oil pan perimeter bolts are much lighter—often 7–10 ft-lb (9–14 N·m) for M6 bolts; tighten in a crisscross pattern and do not over-torque, especially with aluminum or composite pans. Clean mating surfaces, avoid sealant unless specified, and verify thread pitch if replacing a plug (e.g., M14×1.5 is common but not universal).

Tools You Might Need

Having a small set of targeted tools covers most oil pan and drain plug jobs efficiently and safely.

• Metric sockets: 13–19 mm, especially 14 mm and 15 mm.
• SAE sockets: 1/2″ and 9/16″ for older/domestic cases.
• Hex/Allen bits: 6 mm and 8 mm for recessed drain plugs.
• External Torx sockets: E10/E12 for select European oil pans.
• Torque wrench: one in ft-lb for drain plugs and one in in-lb or low ft-lb for pan bolts.
• New crush washer or sealing washer (vehicle-specific).
• Drain pan, gloves, shop towels, and brake cleaner for cleanup.

This compact toolkit will handle the vast majority of oil changes and oil pan removals on modern vehicles.

Summary

There’s no single socket size for an “oil pan.” For the oil drain plug, most vehicles use 13–17 mm—most commonly 14 mm or 15 mm—with occasional 19 mm or 6/8 mm internal hex. If you’re removing the oil pan itself, expect mainly 10 mm bolt heads, with some 13 mm or external Torx on certain European models. Verify the exact size for your vehicle and use proper torque to avoid leaks or damage.

What tool should you use to loosen the oil pan drain plug?

Play. So let’s go ahead open it up really quick. Yeah we’re going to use some tin snips why. Not cuts right through. There. And there we go just a little flexible dongle deal thingy.

What size is the bolt for the oil pan?

There is no universal size for an oil pan bolt; the correct size depends on the specific make and model of your vehicle, which can be a metric size (like M8, M12) or an imperial size (like 1/4-inch or 5/16-inch). To find the right size, you must consult your car’s owner’s manual or a vehicle-specific repair guide, or if replacing a bolt, use a proper-sized wrench or socket to remove the old one and match its specifications.
 
How to Determine the Correct Bolt Size

1. Check Your Vehicle’s Owner’s Manual: This is the most reliable way to find the exact bolt size and thread specification for your car. 
2. Use a Vehicle-Specific Repair Guide: Online resources or a printed manual for your car’s make and model will provide detailed specifications for all components. 
3. Examine the Old Bolt:
   • Metric Bolts: These will be labeled with an “M” followed by a number (e.g., M8, M12), with the number indicating the diameter. 
   • Imperial (SAE) Bolts: These will be specified with a fraction (e.g., 1/4-inch, 5/16-inch) indicating the diameter. 
4. Match the Wrench Size: If you can’t find the exact size, use a wrench that fits the bolt head snugly. A 15mm, 16mm, or 9/16-inch is common for some vehicles. 

Common Bolt Types and What They Mean

• Bolt Head Size: The size of the wrench needed to turn the bolt (e.g., 3/8 inch). 
• Thread Size: The diameter and pitch of the threads on the bolt. For example, a 5/16-18 bolt has a 5/16-inch diameter and 18 threads per inch. 
• M8 x 1.25 x 25: A common way to describe metric bolts. The “M” indicates it’s metric, “8” is the diameter in millimeters, “1.25” is the thread pitch, and “25” is the length in millimeters. 

Important Considerations

• Bolt Length: Opens in new tabNot all holes are the same depth, so always check the depth of the bolt holes to ensure you use the correct bolt length for each one. 
• Gaskets: Opens in new tabThe oil pan often uses a gasket to prevent leaks. Using the correct size bolt with the proper gasket is essential. 

What size socket is a oil pan plug?

There is no universal oil pan socket size; the specific size depends on the vehicle’s year, make, and model, but common sizes include 15mm, 16mm, or 9/16-inch. To find the correct socket, you’ll need to check your vehicle’s manual or visually inspect the drain plug itself, as a proper fit is crucial to avoid rounding the bolt head. 
How to find the right socket size:

1. Check your vehicle’s manual: or a reliable parts website for your specific car. 
2. Visually inspect the drain plug: before you start your oil change. The size of the wrench needed corresponds to the width across the bolt’s flats. 
3. Have a basic metric socket set: on hand, as common sizes range from 10mm to 21mm, with 15mm being a frequent choice. 

Tips for success:

• Use the correct size: A socket that is too small can damage the bolt head, while one that is too large can also cause issues and damage. 
• Use a 6-point socket: This type provides a more secure fit on the bolt head, reducing the risk of stripping. 
• Clean the bolt and pan: Ensure the bolt and surrounding area are clean before reinstalling to maintain a proper seal and prevent future leaks. 
• Consider writing it down: For future reference, note the drain plug size under the hood of your car. 

What socket size do I need for an oil change?

You need a socket wrench (14mm or 15mm), an oil filter wrench, an oil drain pan, a funnel, and a new oil filter.