Over torquing lug nuts can cause:

Over-torquing lug nuts can cause damage to wheel studs because applying excessive force can lead to the stretching or even the shearing of the studs. Wheel studs are designed to hold the wheel securely in place, but when they are subjected to torque levels beyond their specifications, it can compromise their structural integrity. This damage might not be immediately visible, but it can result in a failure of the studs to secure the wheel properly, potentially leading to more severe issues like the wheel loosening or detaching while driving.

The other options are not accurate implications of over-torquing lug nuts. For example, while poor fuel economy could arise from a variety of factors related to wheel alignment or drive train issues, it is not a direct consequence of improperly torqued lug nuts. Improved fuel economy is counterintuitive to any mechanical damage and would not result from over-tightening. The statement about the wheel falling off can happen if wheel studs are damaged due to over-torquing, but it’s the damage to the studs that creates that risk, not a result of direct over-torque itself. Thus, the primary and most direct impact of over-torquing is indeed the damage to the wheel studs.