For those of you who run spacers with your wheels make sure the lug-nuts engage the proper amount of threads on the wheel studs.
I came VERY close to loosing the passenger side rear wheel recently. I was about to attend a local Cars & Coffee event but when I backed my Vette out of the garage I heard an odd sound from the rear. As I pulled it back into the garage I heard that same sound. I looked under the car at the rear suspension and nothing looked obviously wrong. I decided not to drive it but as I was closing the garage door I noticed something shiny on the drive way. I found 2 lug-nuts (first pic), each with the wheel studs sheared off. I started walking around my car and found the rear passenger side wheel only had 1 lug-nut left (2nd pic), and 4 studs missing. I torqued all 4 wheels myself with my torque wrench to 75 ft-lbs (67 factory spec), when I installed them. This happened with approx. 1,000 of miles on the wheels.
Lugnut/stud pic
Wheel pic
It took me a while to figure out what caused the problem. The (4) wheel studs were sheared off flush with the spindle outer surface. The cause was shear stress caused by the lug-nuts only engaging about ¼” of wheel stud threads due to the ¼” spacers I installed.
The tire/wheel/lug-nut vendor I used, ASME and NHRA all recommend that lug nuts should engage a minimum length of threads equal to the diameter of stud. In my case 7/16".
The vendor I purchased my wheels/tires/lug-nuts from near the end of 2018, while body was still off the frame, acknowledged that when they sent me spacers, to cure a wheel/caliper interference issue, they should have also sent me Extended Thread MAG E/T Tapered lug-nuts & locks to replace the ones they had originally sent with the wheels/tires.
Figuring that all the wheel studs have been stressed I've replaced them all. Just a heads up for anyone else running or thinking about running spacers.
I came VERY close to loosing the passenger side rear wheel recently. I was about to attend a local Cars & Coffee event but when I backed my Vette out of the garage I heard an odd sound from the rear. As I pulled it back into the garage I heard that same sound. I looked under the car at the rear suspension and nothing looked obviously wrong. I decided not to drive it but as I was closing the garage door I noticed something shiny on the drive way. I found 2 lug-nuts (first pic), each with the wheel studs sheared off. I started walking around my car and found the rear passenger side wheel only had 1 lug-nut left (2nd pic), and 4 studs missing. I torqued all 4 wheels myself with my torque wrench to 75 ft-lbs (67 factory spec), when I installed them. This happened with approx. 1,000 of miles on the wheels.
Lugnut/stud pic
Wheel pic
It took me a while to figure out what caused the problem. The (4) wheel studs were sheared off flush with the spindle outer surface. The cause was shear stress caused by the lug-nuts only engaging about ¼” of wheel stud threads due to the ¼” spacers I installed.
The tire/wheel/lug-nut vendor I used, ASME and NHRA all recommend that lug nuts should engage a minimum length of threads equal to the diameter of stud. In my case 7/16".
The vendor I purchased my wheels/tires/lug-nuts from near the end of 2018, while body was still off the frame, acknowledged that when they sent me spacers, to cure a wheel/caliper interference issue, they should have also sent me Extended Thread MAG E/T Tapered lug-nuts & locks to replace the ones they had originally sent with the wheels/tires.
Figuring that all the wheel studs have been stressed I've replaced them all. Just a heads up for anyone else running or thinking about running spacers.
