What size are my wheel nuts?

Wheel nuts (lug nuts) do not have a universal size; the correct size depends on your vehicle's make, model, and year. Most modern passenger cars use metric lug nuts with threads around M12 or M14 and a hex size of 19mm or 21mm, but you should verify your exact specification for safe installation and proper torque.

Understanding lug nut size matters for safety and performance. Using the wrong size can damage studs or nuts, cause improper seating, or lead to wheel detachment. The following guide helps you identify the correct lug nut size for your vehicle and provides typical ranges you might encounter in practice.

Identify your lug nut size for your vehicle

To determine the exact lug nut size for your car, follow these steps. Each step helps ensure you get the right diameter, pitch, seat, and head size so you can purchase the correct nuts or replacements.

1. Check the vehicle’s documentation or the door jamb placard for wheel and lug nut specifications, especially the recommended lug nut size and torque. Some manufacturers print lug nut specs on the owner’s manual or the sticker near the driver's door.


2. Inspect the lug nuts and wheel studs. Look for stamped markings on the lug nut head that indicate the thread size (for example, M12x1.25 or M14x1.5) and the seat type.


3. Measure the hex size of the lug nut using a metric or imperial wrench or socket. Common hex sizes are 19mm, 21mm, or in imperial equivalents like 9/16" or 5/8".


4. Determine the thread diameter and pitch. If you can remove a lug nut, measure the stud diameter (roughly 12mm or 14mm for metric M12 or M14) and use a thread gauge or calipers to confirm pitch (such as 1.25 or 1.5).


5. Identify the seating style of the lug nut. The most common is the 60-degree conical (taper) seat, but some vehicles use ball seat or flat seats. The seat type must match your wheel’s lug hole design.


6. If you have aftermarket wheels or a wheel with a locking lug nut, verify compatibility with the wheel manufacturer’s recommendations and ensure you have the correct locking key or replacement.

Accurate measurement and verification are key. If you’re unsure, contact the vehicle manufacturer, a dealer, or a trusted automotive technician with your VIN, year, make, and model to confirm the exact lug nut size and torque specification.

Common lug nut sizes and appearances you may encounter

While your exact spec should come from official documentation or measurements, these sizes are commonly seen on many modern cars and light trucks. Use this as a reference only and always verify for your specific vehicle.

• M12x1.25 threads with a 19mm hex head (very common on many recent passenger cars)


• M12x1.5 threads with a 19mm hex head (also common on many modern vehicles)


• M14x1.5 threads with a 21mm hex head (found on some larger cars and SUVs)


• Imperial/US-style lug nuts on older or certain models, often with 9/16" (14.3mm) or 5/8" (15.9mm) hex heads

Knowing the seat type and thread pitch is as important as the diameter and hex size, since mismatched seats or threads can damage wheels or studs and prevent proper seating and torque.

Practical tips for replacement and safety

Locking lug nuts and missing keys

Some vehicles use locking lug nuts that require a specific key. If the key is lost, you’ll need to contact the dealer or a locksmith with proof of ownership to obtain a replacement screw or key compatible with your wheels.

Torque specifications

Always install lug nuts to the manufacturer’s specified torque. Over-tightening can stretch studs or warp wheels; under-tightening can lead to wheel loosening. Refer to your owner’s manual or service bulletin for the correct torque value and perform a proper star or crisscross tightening pattern when mounting wheels.

Summary

There is no one-size-fits-all answer to “what size are my wheel nuts?” The exact size depends on your vehicle. Start with official documentation or the door jamb placard, then verify by measuring the lug nut head size, the thread diameter and pitch, and the seat type. Common configurations you may encounter include M12x1.25 or M12x1.5 with 19mm hex heads, or M14x1.5 with 21mm hex heads, plus a subset of imperial sizes on older vehicles. When in doubt, consult a dealer or trusted technician with your car’s make, model, year, and VIN to confirm the precise lug nut size and torque requirements.

What can I do if I've lost my locking wheel nut?

If you've lost a locking wheel nut, you should first check common places it might have been stored and then contact a professional like a tire shop or dealership for removal. If that's not an option, you can try a DIY method of hammering a specialized or 12-point socket onto the nut to remove it. 
Step 1: Search for the key

• Look in common storage spots like the glove box, center console, under the spare tire, or in the trunk.
• Contact the last person or company who worked on your vehicle to see if they have it. 

Step 2: Seek professional removal

• Visit a tire shop or mechanic: These professionals have specialized tools and techniques to remove the nut without damaging your wheel. 
• Contact the dealership: They may be able to get a replacement key or have a procedure for removal. 

Step 3: Use a DIY removal method (if comfortable and the nut isn't a "spinning collar" type)

• Hammer on a socket: Hammer a 12-point socket that is slightly undersized over the locking nut. The socket's edges will bite into the nut, allowing you to use a breaker bar to twist it off. 
• Use a specialized removal tool: You can purchase a wheel lock removal kit that has a spiral groove for better grip than a standard socket. 
• Important: After removing the old locking nuts, replace them with standard lug nuts and ensure they are torqued correctly. 

This video demonstrates how to remove a locking lug nut using a specialized tool and a torque wrench: 54sChrisFixYouTube · Aug 13, 2023
Step 4: After removal

• Once the old locking wheel nut is removed, replace it with a standard wheel nut or purchase a new set to ensure the wheel is secure. 

Is 7/8 the same as 22mm?

No, 7/87 / 87/8 inch is not exactly the same as 222222 mm, but they are very close and often used interchangeably.7/87 / 87/8 inch is equal to 22.2322.2322.23 mm, and 222222 mm is equal to approximately 0.8660.8660.866 inches. 

• 222222 mm: is slightly smaller than 7/87 / 87/8 inch. 
• 7/87 / 87/8 inch: is equal to 22.2322.2322.23 mm. 
• For many applications, a 222222 mm tool will fit on a 7/87 / 87/8 inch fastener, or vice versa, but it might be a bit loose or tight. 
• For a precise fit, you should use the correct size for the fastener you are working with. 

What does M12x1 5 lug nuts mean?

An "M12 x 1.5" lug nut refers to a metric lug nut with a 12mm diameter and a 1.5mm thread pitch. The "M12" indicates the nominal outer diameter of the stud is 12 millimeters, and the "1.5" indicates there is a distance of 1.5 millimeters between each thread. 
You can watch this video to learn more about the importance of lug nut thread engagement: 47sKONIG WHEELS USAYouTube · Apr 3, 2020

• M12: This is the metric size of the stud's diameter, which is 12 millimeters. 
• 1.5: This is the thread pitch, meaning the distance between each thread on the stud is 1.5 millimeters. 
• Importance: This specification is crucial for ensuring the lug nut will properly and securely fit onto the vehicle's wheel stud. Using the incorrect pitch can cause damage to the threads and an improper wheel fit. 

How to find wheel stud size?

Measuring a wheel stud with a vernier caliper will give you the best measurements for buying a new replacement wheel stud. You will need to measure the overall length of the stud, the diameter of the threaded shaft and the diameter of the knurl or collar of the bolt directly under the stud head.