The wheel studs are the threaded bolts (or studs) that protrude through the holes in your wheels onto which you would thread your lug nuts. Most vehicles have either 4 or 5 wheel studs per wheel, however, some trucks, vans or SUV's can have up to 8 per wheel.

Thread Size

You can easily identify your thread size and pitch with a simple thread pitch gauge available at any hardware store, or you can simply take one of your lug nuts to your local hardware store and spin it onto the bolts they have on hand. The thread size or thread diameter is the measurement taken across the outside diameter of your wheel stud threads measured in either standard (7/16", 1/2", etc.) or metric (12mm, 14mm, etc.) dimensions. The most common thread sizes are 10mm, 12mm, 14mm, 7/16", 1/2", 9/16", 5/8". You can find most factory stud sizes in your vehicle owner's manual or you can use online guides (i.e.: http://www.brandsport.com/howdoifirilu.html ).

Thread Pitch

The thread pitch is the measurement of either threads per inch for non-metric studs or the distance in millimeters between the threads for metric applications. This tool will help identify the proper thread pitch that was on the vehicle from the factory. If the vehicle has been modified, you will need to verify the thread pitch. 

Seat Type

The seat type refers to the area where the lug nut actually makes contact with the wheel surface. The most common types are either an acorn/tapered seat, a mag seat (which features a flat seating surface with a separate seating washer) or a ball seat. 

Length/Dimensions

It is critical that you confirm the dimensions of your lug nut or wheel lock to ensure a proper fit for both safety and appearance. This includes the outside diameter, overall length and for Mag style nuts/locks you must also determine the proper shank diameter and shank depth.

Finish/Color

Lug nuts and locks are available in a wide variety of finishes and colors including chrome plated, black chrome, stainless steel, zinc, yellow chromate, silver, red, blue and more. Once you have identified these fitment components it is just a matter of choosing your preferred style of nut or lock. 

Lug Sizes (ISO standard and UN-series types)

• M12 x 1.25
• M12 x 1.5
• M12 x 1.75
• M14 x 1.25
• M14 x 1.5
• M14 x 2.0
• M16 x 1.5
• M16 x 2.0

• 3/8" - 24 UNF
• 7/16" - 20 UNF
• 1/2" - 20 UNF
• 9/16" - 18 UNF