GM Lumina/Grand Prix/Cutlass Supreme/Regal 1988-1996

Wheel Lug Studs


All models use metric wheel nuts and studs. The nut will have the word "metric'' stamped on the face and the stud will have the letter "M'' into the threaded end.

The thread size of the metric wheel nuts and wheel studs are M12 X 1.5, this signifies:

M = Metric
12 = Diameter in millimeters
1.5 = Millimeters per thread


See Figures 1 and 2

Click image to see an enlarged view

Fig. Fig. 1: Use the proper tool to remove the wheel stud(s)

Click image to see an enlarged view

Fig. Fig. 2: Install washers and a nut on the wheel stud, then tighten until the stud is properly seated

Never try to reuse a wheel stud. Once a wheel stud has been removed, discard it and replace it with a new one.

  1. Raise the vehicle and support safely.
  3. Remove the wheel, brake caliper, bracket and rotor.
  5. Cut about 1 / 2 in. (13mm) OFF of the outer end of the stud.
  7. Position the stud at the 6 o'clock position. Use tool J6627-A or equivalent to extract the stud from the hub. Do not hammer on the studs to remove, as this could damage the bearing.

To install:
  1. Clean the hub and place the replacement stud in the hub.
  3. Add enough washers to draw the stud into the hub.
  5. Install the lug nut flat side to the washers and tighten until the stud head seats in the hub flange.
  7. Remove the nut and washers.
  9. Repeat for other studs as required.
  11. Install the brake parts and wheel. Tighten the lug nuts to 100 ft. lbs. (140 Nm).
  13. Lower the vehicle and recheck the wheel nut torque.