Tires are made of many components, and there are aspects of the tire that are constructed independently of others. A tire's construction varies based on the type of tire and the intended use of the tire. One thing remains consistent, however, for tires that maintain traction on different surfaces, whether paved or off-road. Lug treads. Lugs are often referred to as tread lugs, lugged tread, tread blocks, or simply tread. What is Lug Tread? Ultimately, the lug of the tread is the most important gripping aspect of a tire's contact patch. Any tire manufactured for legal use on roadways in the United States will possess a lug. Tread without any design of lugs, or lug patterns, would simply qualify as a slick tire. While such a tire is excellent for use on professional racetracks, it simply does not meet the demands that we put on passenger and commercial transport vehicles on a daily basis. Tread lugs, or lugged tread, offers stability, support, and various performance options and capabilities dependent on the manufacturer's goals for that particular tire. Basically, lugs are the raised portion of a tire's tread. They are uniquely shaped in order to offer performance as well as aesthetic design. Different tires possess lug construction that varies in size, shape, and materials (the rubber compounds they are made of). Tire manufacturers offer multiple tire options. Some are designed for high performance, possessing tread lugs that will offer a smooth rolling resistance, softer compounds for gripping the road, and tire shoulders that may also possess a particular extended lug. Tread on other tires may be designed for off-road use. On these, you'll find firmer tread lugs, knobby tire shoulders, and tread design that's engineered to grip a variety of off-road surfaces. The lug design on off-road tires works to channel mud and other materials away from the tire. Between the lug tread are gaps. These tread pattern gaps are known as the tread voids, or grooves. These voids allow the lugs to flex and form to the road surface below, allowing for maximum traction and maneuverability. Maintaining Lug Tread In order for tires to function as designed and to last longer, they must be routinely maintained. Issues such as improper inflation can wreak havoc on treadwear. Most of know that lug tread wears down, but improper tire inflation may wear them down unevenly. This is true for tires that are overinflated or under inflated. A regular check of tire pressure is one of the easiest ways to maintain the tread life, performance, and safety capability of a set of tires. In addition to tire inflation pressure, routine maintenance tasks such as tire rotations, alignments, and balancing are a necessity. Rotating the tires every 5,000 - 6,000 miles will help ensure that the tread lugs experience even wear. This is especially true for high performance tires. The compounds of these tires are often softer, and regular rotations will greatly increase their mileage capability. Procedures such as alignment and balance will ensure that uneven wear doesn't affect the shoulders or lug patterns on one or more tires. In terms of tire replacement, when a tread lug measures less than 2/32 of an inch, it is definitely time to replace the tire. Some recommendations say that 4/32" is time to replace the tire. There are raised wear bars found in the tread void that will help signify this level. As the tread lugs wear down, they will naturally lose some of their performance capability.