Wheel Lug Wrench
A socket wrench, typically L-shaped or cross-shaped, used to loosen and tighten wheel lug nuts.
A wheel lug wrench (also called a tire iron) is a socket wrench designed specifically for tightening and loosening the lug nuts or lug bolts on vehicle wheels. The most common designs are the L-shaped wrench (which often features a pry bar end on the handle for removing hubcaps) and the cross-shaped 4-way wrench, which features four different socket sizes to fit various vehicles.
Lug wrenches are standard emergency equipment supplied with most vehicles for changing flat tires. The length of the handle is designed to provide sufficient leverage to break loose tight lug nuts by hand. However, because they rely on manual force, it is easy to under-tighten or over-tighten the nuts. Over-tightening can warp brake rotors or stretch and snap the wheel studs, while under-tightening can allow the wheel to loosen during driving.
While a lug wrench is excellent for emergency roadside use, professional mechanics use impact wrenches for fast removal and calibrated torque wrenches for final tightening. Lug nuts should always be tightened in a star or cross pattern to ensure even clamping pressure across the rotor face, preventing runout and brake pulsation.