Technique
Ideally, the nuts (or bolts) should be tightened with a torque wrench. Lug wrenches are much less expensive because they lack the ability to measure or limit the force used. Installing a wheel with a lug wrench thus requires a bit of rough guessing about proper tightness. Excessive force can strip threads or make the nuts very difficult to remove. Also, uneven torque between the various lug nuts, or excessive torque, can lead to warping of the brake rotor if the car is equipped with disc brakes. For this reason, impact wrenches should properly be used only for removing lug nuts, not for tightening them, although in practice this rule is often ignored for convenience's sake, even by professional mechanics.
When re-fitting a wheel, the nuts (or bolts) should be tightened in a criss-cross pattern (to even out the forces) and initially should only be tightened 'finger tight' on all nuts. In this context 'finger tight' is tight enough to reach the point where free play is taken up and proper tightening is about to begin, say, the tightening force using the lug wrench/wheel brace like a screwdriver. This should be repeated twice, to ensure the wheel is properly centred and restrained by all nuts (as often the first nut(s) that is tightened will be slightly loose after completing the set for the first time), then the wheel should be lowered to the ground and the criss-cross tightening pattern repeated to modest torque (say few fingers force on the lug wrench/wheel brace arm), and then finally repeated to full hand force.
Rarely, and more often with large trucks and lorries, insufficient force can lead to the nuts coming undone while in use. Because of this, it is best to use a torque wrench or similar tool to finally tighten the wheel lug nuts to the proper torque specification as soon as possible after using a lug wrench to affix a wheel. At the very least, the lug nuts should be checked for tightness after 50–100 km/miles when things have been subject to some vibration and thermal cycling.
Lug wrenches are known for their use as weapons in cases such as road rage, as they are readily available in most cars, made of metal and heavy enough to cause injury.
Lug wrenches are occasionally mistaken for tire irons, due to the relative rarity of the tire iron, another metal tool of similar size which is not often needed by those who do not work with cars.
Read more about this topic: Lug Wrench
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—Rebecca West (1892–1983)
“The audience is the most revered member of the theater. Without an audience there is no theater. Every technique learned by the actor, every curtain, every flat on the stage, every careful analysis by the director, every coordinated scene, is for the enjoyment of the audience. They are our guests, our evaluators, and the last spoke in the wheel which can then begin to roll. They make the performance meaningful.”
—Viola Spolin (b. 1911)
“The more technique you have, the less you have to worry about it. The more technique there is, the less there is.”
—Pablo Picasso (1881–1973)