What Size Socket Do You Need for an Oil Drain Plug?

There isn’t a single universal size: most passenger vehicles use a 13 mm to 19 mm metric socket—14 mm, 15 mm, and 17 mm are the most common—while some American models use 1/2 in to 3/4 in sockets. Certain European makes and newer plastic drain plugs may require an internal hex (6–8 mm) or Torx bit (often T45). The exact size depends on your vehicle, so check the owner’s manual or verify on the plug before turning a wrench.

Why There’s No One-Size-Fits-All Socket

Automakers choose different drain plug designs and head sizes by engine family, oil pan material, and region. Even within a brand, sizes can vary by model year and engine. That’s why the safest approach is to confirm your specific vehicle’s requirement rather than assuming a standard fits every car.

Common Socket Sizes by Make and Type

The following list summarizes the oil drain plug socket sizes most frequently found across popular brands and vehicle types. Use it to narrow down your options before you crawl under the car, but always verify on your engine to avoid rounding a plug.

• Toyota/Lexus: Often 14 mm external hex.
• Honda/Acura: Commonly 17 mm external hex (frequent across many models).
• Nissan/Infiniti: Often 14 mm external hex.
• Subaru: Frequently 17 mm external hex.
• Mazda: Commonly 17 mm external hex.
• Hyundai/Kia: Often 17 mm external hex.
• Ford (gas engines): Commonly 13 mm or 15 mm external hex, depending on engine family.
• GM/Chevrolet/GMC: Frequently 15 mm; some engines use 13 mm.
• Ram/Chrysler/Jeep/Dodge: Commonly 13 mm or 15 mm on many trucks and SUVs.
• Volkswagen/Audi: Often 19 mm external hex; some models use 6–8 mm internal hex or a T45 Torx on plastic plugs.
• BMW/MINI: Typically 17 mm external hex; some engines use an 8 mm internal hex.
• Mercedes-Benz: Frequently 13 mm external hex; certain applications use an 8 mm internal hex.
• Volvo: Often 17 mm external hex; some later models use a Torx (commonly T45) plastic plug.
• Porsche: Commonly 8 mm internal hex on many models.
• Motorcycles: Usually 12–17 mm external hex, with 17 mm very common; some use 8 mm internal hex.
• Light trucks/heavy-duty: Larger plugs appear more often (e.g., 19 mm), but many half-tons still use 13–17 mm.

These sizes cover the majority of vehicles on the road. However, exceptions exist—particularly with special pans, aftermarket plugs, or plastic “service” plugs—so confirm before applying force.

How to Identify Your Plug Size Quickly

Use this short process to zero in on the correct socket without guesswork or damage.

1. Check your owner’s manual or a service database for “engine oil drain plug” size and torque.
2. Inspect the plug head: determine if it’s an external hex, an internal hex (Allen), or Torx.
3. Test-fit a six-point socket or bit by hand; it should seat fully with no wobble.
4. If you don’t have documentation, start with the likely sizes for your make (e.g., Toyota 14 mm; Honda 17 mm; GM 15 mm; Ford 13/15 mm).
5. Measure with calipers if needed: across flats for external hex, across flats of the recess for internal hex.
6. Confirm removal torque is appropriate and the crush washer is present before loosening fully.

Taking a minute to identify the head type and exact fit helps prevent rounding the plug and saves time if a specialty bit is required.

Tools Worth Having on Hand

A compact, targeted toolkit can handle almost any drain plug you’ll encounter at home.

• Six-point metric socket set: 13, 14, 15, 17, 19 mm.
• SAE sockets: 1/2 in, 9/16 in, 5/8 in, 3/4 in (useful on older American vehicles).
• Internal hex (Allen) sockets: 6, 8, 10 mm.
• Torx bits/sockets: T40–T50 (T45 is common on some plastic plugs).
• 3/8 in and 1/2 in drive ratchets, short extensions.
• Torque wrench covering roughly 15–75 lb-ft (20–100 N·m).
• Crush washer assortment matched to your plug thread (e.g., M12, M14 copper/aluminum).
• Replacement drain plug matched to your vehicle as a backup.

With these pieces, you can correctly fit, remove, and torque nearly any automotive drain plug you’re likely to encounter.

Tips to Avoid Damage and Leaks

These best practices reduce the risk of rounded heads, stripped pans, and seepage after the oil change.

• Use six-point sockets to minimize rounding; avoid adjustable wrenches on tight plugs.
• Seat the socket fully and apply steady force; don’t pry at an angle.
• Replace the crush washer each service if your plug uses one (very common).
• Torque to spec: most passenger-car plugs land around 20–35 lb-ft (27–47 N·m); many Hondas are ~29 lb-ft, Toyotas ~27–30 lb-ft, Subarus ~31 lb-ft—always verify for your engine.
• Thread the plug by hand first to avoid cross-threading; then torque.
• If the head is already rounded, use a bolt extractor socket rather than forcing a standard socket.
• Inspect for seepage after warm-up; retorque gently if needed, but never overtighten.

Following these steps protects the oil pan and ensures a reliable seal, which is just as important as the correct socket size.

Quick Reference: Typical Head Sizes by Plug Thread

Head size isn’t identical to thread size, but these pairings are frequently seen on modern vehicles and can guide your selection.

• M12 drain plugs: commonly 14 mm or 17 mm head.
• M14 drain plugs: commonly 17 mm or 19 mm head.
• 1/2 in–20 plugs (SAE): often 9/16 in or 5/8 in head.
• Internal hex designs: usually 6 mm or 8 mm Allen.
• Plastic service plugs: often Torx T45 (varies by manufacturer).

Because manufacturers mix thread and head sizes, treat these as typical—not guaranteed—combinations, and verify on your specific vehicle.

Summary

Most oil drain plugs on passenger vehicles use a 13–19 mm socket, with 14 mm, 15 mm, and 17 mm the most common; some American models lean to 1/2–3/4 in, and certain European or newer plastic plugs require 6–8 mm internal hex or a T45 Torx. Confirm the head type, test-fit a six-point socket, and follow proper torque and washer replacement to prevent leaks and damage. When in doubt, consult your owner’s manual or a service database for your exact engine and model year.

What size wrench do I need to remove the drain plug for an oil change for a 2008 Honda CRV?

And then we want to make sure stick a drain bucket underneath. Let it drain. Out this oil doesn’t look too. Bad. It’s still get a little bit of color to it.

What size socket to remove oil drain plug?

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 do you need for oil?

Ratchet and Socket Set
Get a set that includes some metric and SAE sizes, and if you’re starting out, a 3/8” drive should do just fine. Ratchets and sockets also come in 1/4, 1/2″, 3/4″, and 1” drives. Many medium sized kits will include ratchets and sockets in 3/8” and 1/2″ drive.

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.