Ability to Diagnose: Failed Car Security Wheel Locks

My 2020 Niro EVs came with security wheel locks that require a special security key for removal.  I used them on both the summer and winter tires, although the winter tires are on steel rims which are probably not worth stealing.  When I switched to a 2025 Niro EV in the fall of 2024, I kept the old winter tires.  Everything was fine after three tire changes, but when I re-torqued the tires to 120 Newton-meters a week later, the center of the wheel locks on both rear tires broke off and remained in the security key. 

The dealership claimed I over-tightened the wheel nuts or misaligned the key, and offered to remove the wheel locks for a hefty price.  The security key seemed to 'seat" in the locks but initially would pop off when I tried to remove the lock.  I found that rotating the key slightly would let it seat better, allowing me to remove the failed wheel locks and replace them with the original wheel nuts.

Internet searches did not provide answers as to why the wheel locks failed.  I sent the image above showing the outside and inside of the broken centre sections to McGard who makes the security wheel locks.  Their technician noticed the silver ring on the inside (upper right in image), which suggested that the wheel lock had "bottomed out" on the stud.  McGard claimed that wheel locks are designed for original equipment aluminum wheels, not steel rims.  

I can be hard on "customer service" - it was great to get a quick and definitive answer from McGard.  It never occurred to me that the stud may have forced out the centre section.  The dealer had mounted the snow tires on the 2020 Niro EV with the wheel locks, I found no references to this restriction in my Internet searches, and the problem only occurred after 11 wheel changes.  It is possible that the wheel studs on the 2025 Niro EV are slightly longer than on the 2020 Niro EV, or the 2025 wheel locks have slightly less thread depth.  I will continue using the remaining two wheel locks with the summer tires but will switch to the regular wheel  nuts when I install the snow tires.