Ultimate Guide to Lug Nuts
Looking for information on lug nuts? Our guide explains everything you need to know about these small but important components of your vehicle's wheels. From the different types of lug nuts to how to properly install and maintain them, we have got you covered. Read on to learn more and ensure your wheels stay securely attached while you are on the road.
What is a Lug Nut?
Lug nut is a type of fastener that is used to secure a wheel to the hub of a vehicle. They are typically made of steel or another durable metal and have a threaded interior that allows them to be screwed onto the studs of the wheel hub. Lug nuts are important for keeping the wheel securely attached to the vehicle, and should be tightened to the manufacturer's specifications using a torque wrench. It is also crucial to periodically check the lug nuts for tightness, as they can become loose over time or due to vibrations while driving. Improperly tightened or loose lug nuts can lead to wheel wobbling, vibration, and even the loss of a wheel while driving, which can be extremely dangerous.
Lug nuts are more common in wheel applications than lug bolts.
Lug Nut Types
There are several types of lug nuts used in wheel applications. Most common lug nut types include acorn or cone seat, spherical or ball seat, flat seat, mag seat, spline drive and tuner.
- Conical lug nut or acorn lug nut is the most common type of lug nuts. The conical shape with a wider base allows it to fit snugly into the matching conical seat in the wheel, creating a secure connection. Conical lug nuts are used on a wide range of passenger vehicles.
- Extended thread lug nut has a longer thread and allows the nut to screw onto the wheel stud further, providing additional engagement and increasing the strength of the connection between the wheel and the hub. Extended thread lug nuts are commonly used in high-performance applications where the wheels are subjected to significant stress and loads, such as racing cars, off-road vehicles, and heavy-duty trucks. They are also useful in situations where the hub has been damaged or the stud has been shortened. Extended thread lug nuts can be open-ended, closed-ended and bulge acorn. Open-ended nuts are typically used with racing wheels that have large center holes, while closed-ended nuts are used with wheels that have smaller center holes. Bulge acorn nuts are used with wheels that have recessed lug holes.
- Spherical lug nut or ball seat lug nut has a spherical shape that conforms to the round shape of the wheel's lug hole. This creates a tighter and more uniform fit, reducing the chances of the wheel coming loose while driving. Spherical lug nuts are commonly used in racing and high-performance applications where precise wheel fitment is critical. They are often made from high-strength materials such as titanium or chrome-moly steel to withstand the high stresses and forces generated during racing.
- Mag seat lug nut has extended thread with a flat washer seat, making them sit tightly flush against the wheel. Sometimes mag seat lug nuts will come with actual washers. The term "mag seat" refers to the lug nut's original design for use with magnesium wheels. Magnesium wheels are known for their lightweight and high strength, but they require special lug nuts that are less likely to cause damage to the softer metal of the wheel. Mag seat lug nuts were developed to meet this need and have since been adopted for use with other types of wheels as well.
- Flat seat lug nut has a flat seating surface instead of a tapered one. It is commonly used in wheels that have a flat or chamfered lug nut seat area.
- Tuner lug nut is designed to be smaller and more lightweight, featuring a unique design with a tapered end that provides a snug fit on the wheel stud. These lug nuts are commonly used with aftermarket wheels that have smaller and tighter lug nut openings. To tighten or loosen tuner lug nuts, a lug nut key is required.
- Spline drive lug nut is designed with a series of splines or ridges on the interior of the nut, which correspond to similar ridges on the exterior of the lug nut socket. This design provides a more secure grip and reduces the likelihood of the lug nut slipping or stripping. Spline drive lug nuts are commonly used on aftermarket wheels, particularly those that require a thinner lug nut due to the design of the wheel. Like tuner lug nuts, spline drive lug nuts require a special lug nut key.
If you want to protect your wheels from theft, consider using wheel locks - specially designed lug nuts with a unique pattern that requires a special key to loosen or tighten it.
It is crucial to always use the correct type of lug nut for your specific vehicle and wheel application to ensure proper fitment and safety.
Lug Nut Sizes
The size of a lug nut can vary depending on the make and model of the vehicle. Lug nuts are typically measured in terms of their hex size, thread size, thread pitch, overall length and width.
To determine the correct size of your lug nuts, you can consult your vehicle owner's manual or contact the manufacturer. You can also use a thread gauge to measure the thread size and pitch of the lug nut or take the lug nut to an automotive parts store to be measured or matched with a replacement.
Hex Size
The hex size of a lug nut refers to the width across the flats of the hexagonal or spline head of the nut, and it determines the size of the socket or wrench needed to tighten or loosen the lug nut. The hex size of a lug nut can vary depending on the make and model of the vehicle. Most common hex sizes include 17mm, 19mm, 21mm and 22mm. It is important to use the correct size socket or wrench when working on your vehicle's lug nuts to avoid damaging the nuts or the wheels.
Thread Size
Lug nut thread size is the measurement taken across the inside diameter of the nut thread. It should the same as the thread size of a stud of the wheel hub. It can be measured in inches (1/2") or metric (M12) dimensions. The most common thread sizes are 10mm, 12mm, 14mm, 7/16", 1/2", 9/16" and 5/8".
Thread Pitch
The thread pitch of a lug nut is the measurement of threads per inch for US standard wheel applications or the distance in millimeters between the threads for metric applications. So, for US lug nut a thread pitch of 20 would indicate 20 threads per inch. While a metric lug nut with a 1.75 thread pitch would indicate a gap of 1.75 millimeters between each thread. Thread size and thread width are shown together like 9/16"-18 or M14x1.5. Picking the wrong thread pitch will cause the lugs to pinch when tightening and not engage fully.
Overall Length
Overall length of a lug nut includes the wheel mounting surface, the thread portion and the head of the nut. Ensure that the lug nut is not too long or too short for your wheel and hub application.
Overall Width
Overall width of a lug nut is the measurement taken across the outside diameter of the nut at its widest points.
Most Common Lug Nut Sizes
Here are the most common lug nut sizes for cars and light trucks.
| M14x2.0 | Buy Now |
| M14x1.5 | Buy Now |
| M14x1.25 | Buy Now |
| M12x1.75 | Buy Now |
| M12x1.5 | Buy Now |
| M12x1.25 | Buy Now |
| 1/2"-20 | Buy Now |
| 5/16"-18 | Buy Now |
| 7/16"-20 | Buy Now |
| 9/16"-18 | Buy Now |
How Many Lug Nuts My Wheel Needs?
The number of lug nuts needed to secure the wheel depends on the bolt pattern on your vehicle. Most commonly used are 4-lug bolt pattern, 5-lug bolt pattern, 6-lug bolt pattern and 8-lug bolt pattern. Some vehicles also use 3-lug bolt pattern or 7-lug bolt pattern. It is important to confirm the exact bolt pattern for your vehicle before installing new wheels. You can also check the correct lug bolt pattern designated by vehicle's manufacturer in the vehicle owner's manual.
Where to Buy Lug Nuts?
You can get the best prices on quality wheel lug nuts on Amazon and eBay.
How to Install Lug Nuts
To install lug nuts, you will need a torque wrench. For a step by step lug nut installation guide see how to install lug nuts.
All listed guides, data and/or calculations are for informational purposes only. LugBoltPattern.com does not warrant or make any representations regarding the accuracy of or the results of the use of this information.