GM Service Manual Online
For 1990-2009 cars only

To identify metric wheel nuts and metric wheel studs look for the following:

    • Identify the metric wheel nut by locating the word Metric stamped on its face.
    • Identify the metric wheel stud by locating the letter M stamped into the end of the wheel stud.

The thread size of the metric wheel nuts and the metric wheel studs are indicated by the following example: M12 x 1.5

    • M = Metric
    • 12 = Diameter in millimeters
    • 1.5 = Millimeters per thread (gap between)