In many jurisdictions, the use of winter tires is mandatory. Additionally, many insurance companies extend a discount for their use, required or not. Changing your own tires with the right tools is a snap, and not only saves you money but also the hassle of making an appointment and waiting for the work to be finished.
While everyone understands the problem presented by a loose nut, is it less common to recognize that "too tight" can be just as problematic. A torque wrench lets you know when you have tightened a nut appropriately. This 24" long 1/2"-drive wrench can be adjusted to signal an applied torque from 50 to 250 lb·ft;* the typical torque setting for lug nuts on a passenger vehicle is between 60 and 160 lb·ft, with most in the range of 80 to 100 lb·ft. Just set the desired torque by holding the shaft and turning the handle to the correct setting, and tighten the nut as you would using a regular socket wrench. When you reach the correct torque, the head will click and slip – a tactile and audible signal that you're done.
*Accurate to ±4%.