Wednesday, November 6, 2013
Wheel Lug Nut Torque Specifications
There are three basic types of wheel lug nuts: conical; mag or shank style; and ball seat or spherical. When replacing a wheel or lug nuts, it is important that the correct lug nuts are used. The thread diameter, pitch and seat of different types of lug nuts are not the same and they are not interchangeable. Proper installation of a wheel requires that the lug-nut torque be set to the recommended specification for your vehicle to prevent damage.
Torque Specification Conditions
Torque specifications are for clean, dry threads that are free of dirt. Never apply anti-seize lubricants to the threads of a lug nut unless directed to do so. The use of anti-seize lubricants can result in inaccurate torque values that may cause over torquing and damage to the lug nuts or vehicle rotors and brake drums.
Lug Nut Specifications
The thread or shank diameter of a lug nut is the diameter of the stud part of the lug nut measured across the shank from the outer edges of the threads. Thread-pitch can mean the number of threads per inch, or if listed in millimeters, the distance in millimeters between the threads. The seat is the area on the wheel where the lug nut will tighten down.
Typical Torque Values
The proper torque specification for your vehicle can be found in your owners manual or your vehicles shop manual. If you cannot find the proper torque specification, the following values can be used until your vehicles exact torque value can be confirmed. You will need to know the shank diameter of your lug nut to find the typical torque range.
(Shank diameter) = (Torque range in foot-pounds)
12 mm = 70 to 80
14 mm = 85 to 90
7/16 inches = 70 to 80
1/2 inches = 75 to 85
9/16 inches = 135 to 145
5/8 inches = 125 to 135
