What Size Bolt Is Needed to Change Oil?

There isn’t a single universal bolt size for oil changes. Most passenger vehicles use a hex drain plug that takes a 13–17 mm socket (with M14 x 1.5 threads being very common), but sizes vary by make, model, engine, and oil pan material. Always verify in the owner’s manual or with a thread gauge before buying a replacement plug or crush washer.

Why There’s No One-Size-Fits-All Oil Drain Plug

Automakers use different drain plug designs depending on engine family, oil pan material (steel vs. aluminum), serviceability, and regional standards (metric vs. SAE). Even within a brand, drain plug dimensions and torque specs can change across model years or engines. As a result, the “size you need” may refer to two separate things: the socket size (to remove the plug) and the thread size/pitch (to buy a replacement plug or crush washer).

Typical Sizes by Brand and Vehicle Category

The following list outlines common, but not guaranteed, drain plug socket and thread sizes frequently found on modern vehicles. Use it as a starting point and confirm for your specific VIN.

• Toyota/Lexus: Often 14 mm socket; common thread M14 x 1.5; aluminum crush washer ~14 mm ID.
• Honda/Acura: Often 17 mm socket; common thread M14 x 1.5; aluminum crush washer ~14 mm ID.
• Nissan/Infiniti: Often 14 mm socket; common thread M14 x 1.5; aluminum crush washer ~14 mm ID.
• Subaru: Often 17 mm socket; common thread M16 x 1.5; crush washer ~16 mm ID.
• Ford (gas pickups/crossovers): Frequently 15 mm socket; common thread M14 x 1.5; some newer models use plastic, single‑use drain plugs.
• GM/Chevrolet/GMC: Frequently 15 mm socket; common thread M14 x 1.5 on many V8s; verify per engine code.
• Volkswagen/Audi: Often 19 mm external hex or 6–8 mm internal hex; many use M14 x 1.5; some require single-use plugs/seals.
• BMW/MINI: Often 17 mm external hex or internal hex; many late models use single-use plastic plugs with integrated seals.
• Mercedes-Benz: Mix of 13–17 mm external hex and internal hex designs; thread commonly M14 x 1.5; some engines are serviced via oil extraction.
• Older American vehicles: May use SAE heads (1/2″, 5/8″) and corresponding imperial threads; confirm before purchase.

These patterns cover a large share of vehicles on the road, but exceptions are common—especially with performance models, diesels, and vehicles with composite or plastic oil pans.

Common Socket and Thread Sizes You’re Likely to Encounter

If you’re assembling a basic kit for routine oil changes across multiple vehicles, these socket and thread sizes are the most frequently encountered on modern cars and light trucks.

• Frequent socket sizes (hex head): 13 mm, 14 mm, 15 mm, 17 mm, 19 mm
• Occasional SAE head sizes: 1/2″, 5/8″
• Internal hex (Allen) drivers found on some European models: 6 mm, 8 mm

A compact metric socket set (10–19 mm), plus 6 mm and 8 mm Allen sockets, covers most scenarios; add 1/2″ and 5/8″ sockets if you service older U.S. vehicles.

For replacement drain plugs and crush washers, thread size/pitch matters more than the socket size. These are the thread specs you’ll most often see:

• M12 x 1.25 or M12 x 1.5 (less common for main oil drain plugs, but used on some small engines)
• M14 x 1.25 (occasional), M14 x 1.5 (very common)
• M16 x 1.5 (common on Subaru and some others)

Match crush washer inner diameter to the plug thread (e.g., M14 plug with ~14 mm ID washer). Some plugs use molded or captive seals and are single-use—replace them every oil change.

How to Identify Your Exact Drain Plug Size

To avoid rounding off a plug or buying the wrong replacement, follow this quick identification process.

1. Check the owner’s manual or a factory service manual for drain plug thread and torque spec.
2. Use a caliper and thread gauge (or take the plug to a parts store) to confirm diameter and pitch (e.g., M14 x 1.5).
3. Test-fit sockets snugly by hand before applying force; the correct socket should not wobble.
4. Inspect and replace the crush washer or seal; never stack washers.
5. Tighten with a torque wrench to the specified value to prevent stripping aluminum pans.

These steps minimize risk of leaks, stripped threads, or damaged plugs—common pitfalls when guessing at sizes.

Torque Guidelines and Washer Notes

Overtightening is a leading cause of stripped pans and leaks. When in doubt, use a torque wrench and new washer.

• Typical torque ranges for passenger cars: roughly 20–35 ft‑lb (27–47 N·m), depending on plug and pan material.
• Aluminum pans are more sensitive; stay at the lower end of the range if a precise spec isn’t available.
• Always replace single-use aluminum or fiber crush washers; copper washers can sometimes be annealed but are inexpensive to replace.

Refer to the exact spec for your engine. If you don’t have it, err on the conservative side and verify there’s no seepage after a warm-up cycle.

Special Cases and Caveats

Some vehicles deviate from the standard hex drain plug. Be aware of these variations to avoid surprises mid-service.

• Plastic or one-time-use plugs (e.g., newer BMW/MINI and some Ford applications) require replacement each oil change.
• Internal hex (Allen) or Torx drain plugs are common on certain European models; have the correct driver sizes on hand.
• Top-side extraction: Select Mercedes, BMW, and others can be serviced from the dipstick tube with an extractor—verify whether the drain plug even needs removal.
• Aftermarket drain valves (e.g., Fumoto) have their own thread requirements; match to your OEM thread spec.

Checking service information for your specific engine beforehand saves time and prevents damage, especially with single-use plugs and composite pans.

Quick Reference Examples (Verify for Your VIN)

These examples reflect common configurations for popular models and are provided as general guidance only.

• Toyota Camry 2.5L (2012–2024): typically 14 mm socket; M14 x 1.5 thread; aluminum crush washer (~14 mm ID).
• Honda Civic 1.8L/2.0L (2006–2021): typically 17 mm socket; M14 x 1.5 thread; aluminum crush washer (~14 mm ID).
• Subaru Forester/Outback 2.5L FB engines: typically 17 mm socket; M16 x 1.5 thread; crush washer (~16 mm ID).
• Ford F‑150 (5.0L V8, many years): frequently 15 mm socket; M14 x 1.5 thread; some late models use single‑use plastic plugs.
• Chevrolet Silverado 1500 5.3L: frequently 15 mm socket; M14 x 1.5 thread; aluminum crush washer.
• VW/Audi 2.0T (various): often 19 mm external hex or 6–8 mm internal hex; commonly M14 x 1.5; many specify a single-use plug/seal.

Always confirm with the service manual or a parts lookup by VIN; mid-cycle changes and engine options can alter plug and washer specs.

Summary

There is no universal “bolt size” for changing oil. Most cars use a drain plug that takes a 13–17 mm socket and often features M14 x 1.5 threads (with M16 x 1.5 common on Subaru and others). Verify the exact socket size, thread pitch, and torque spec in your owner’s manual or via a thread gauge, replace the crush washer, and tighten to spec—especially with aluminum or composite oil pans.

What size socket is needed for an oil change?

There isn’t a single socket size for all oil plugs; the correct size depends on your vehicle’s make, model, and year. Common sizes include 17mm and 14mm for many Japanese and European cars, but you might need to check your vehicle’s specifications or visit an auto parts store for help. A 6-point socket is recommended for better grip to avoid stripping the bolt head. 
How to find the right socket size

1. Check your vehicle’s manual: The most reliable way is to consult your car’s owner’s manual to find the specific drain plug size. 
2. Identify the head type: Most drain plugs have a hex-shaped bolt head. 
3. Measure the bolt head: If you have a socket set, try a few sizes to see which one fits snugly. 
4. Consult an auto parts store: Bring the vehicle information to an auto parts store, and they can look up the specific size for you. 
5. Consider common sizes: While not universal, many Japanese and European cars use metric sizes, with 17mm and 14mm being common. 

Tips for changing the oil plug

• Use a 6-point socket: This type of socket is more effective at gripping the bolt and prevents the head from getting rounded off. 
• Use a 3/8-inch drive socket and ratchet: This is a common size for most DIY oil changes. 
• Have a replacement plug ready: If the old drain plug is worn or stripped, you’ll need a new one to replace it. 

What size socket is an oil pan bolt?

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 is the size of oil drain bolt in MM?

The most common sizes for drain plugs are typically in the 14mm to 19mm range.

What size is the oil change bolt?

There isn’t a single “oil change bolt size” because sizes vary by vehicle. To find the correct size for your car, you must identify the specific drain plug bolt head size for your vehicle’s make and model. You can typically use a socket wrench set with common metric sizes like 14mm, 15mm, 17mm, or 19mm. If you don’t know the size, you can buy a vehicle-specific part or use a tool to measure the bolt, such as digital calipers, but a wrench that is too small can strip the head. 
How to Find the Right Size

1. Check Your Vehicle’s Owner’s Manual: Opens in new tabYour manual will often have the specific size of the drain plug. 
2. Consult an Auto Parts Store: Opens in new tabTell the store your vehicle’s year, make, and model, and they can look up the correct size. 
3. Measure the Bolt: Opens in new tabIf you have calipers or a ruler, you can measure the width of the bolt head to determine its diameter. 
4. Test Common Socket Sizes: Opens in new tabIf you don’t know the size, you may have to try the common metric socket sizes in the 14mm to 19mm range. 

Important Tips

• Use the Correct Tool: Use a socket or wrench that fits the bolt head snugly to avoid stripping it. 
• Replace the Washer: Always use a new crush washer when reinstalling the drain plug to prevent leaks. 
• Use a Proper Socket: For best results, use a 6-point socket, as these provide a more secure grip than 12-point sockets and reduce the risk of stripping.