100 Nm equals 73 Lbs. Ft.. If the wheel nuts were tightened to 100 Nm they were under tightened! There may be a need to check the accuracy of the torque wrench involved here. 100 Lbs. Ft. equals 135 Nm. I don't have an Owners Manual in front of me now but if both values are listed for wheel nut torque, (135 Nm/100 Lbs. Ft.) a person may have accidently tightened the wheel nut to 135 Lbs. Ft.! Mistakes happen! That would probably break the wheel studs.