Conditions Affecting Tire Wear and Tire Mileage
There is always a trade off between performance and tread life in the development of tires. To gain one thing you have to trade off something else. Some brag when they get 15000 miles out of a set of tires because they understand how hard they drive while others complain if they get 40 to 50000 miles. The next paragraph explains many things someone can do to improve mileage regardless of how they drive, the type of tire, or the power of their truck.
Tread life is related to many factors some of which are; the air pressure maintained, how often air pressure is checked, rotation, driving habits, road surfaces, road conditions, suspension setup, caster and tow alignment, shock absorbers, etc. There is a relationship between the size tire used and the weight of the truck.. .the larger the tire and the lighter the truck the better the mileage tends to be and the smaller the tire and the heavier the truck the less the tread life will be. One of the worst mistakes made is neglect of air pressure. Air pressure should be checked at least once a month with an accurate gauge and checked when the tires are cool. Two things support the weight of a vehicle...the actual air pressure and the volume of air in a tire. When a big tire is used the larger volume of air will support the vehicle with very little air pressure but that does not mean the tire is stable. The tire will look like it is under inflated because it does not appear to be low but this low air pressure makes the tire unstable which causes squirming of the tread. It is OK to run tires low off road but the pressure should be bought back up as soon as you put the vehicle back on the highway. It is recommended that tires used on four wheel drive vehicles be rotated front to rear and rear to front about every four to five thousand miles...don't criss-cross.
As you can see from the above there is no way of knowing what tread life a given set of tires will have. The compounds used in the tread rubber also vary but is constant with each type of tire manufactured. Manufacturers try to achieve a balance in tread compounds that will provide good highway traction and overall performance while not sacrificing too much in tread life.
Causes of Tire Wear
Tires provide traction because the weight of the vehicle forces the tread rubber into the road's small surface irregularities. Unfortunately, that same interaction causes wear as the surface tears microscopic pieces of rubber from the tread as it slips into and out of contact with the road. And just as coarser sandpaper removes material faster, coarser road textures cause more tire wear. The following mileage estimate is typical of what a 40000 mile rated tire driven on smother asphalt would deliver if driven exclusively on other road surfaces.
Smooth Asphalt 40000
Coarse Asphalt 36000
Extra Coarse Asphalt 24000
Country Road 20000
Crushed Stone 8000
Wheel alignment controls the distribution of vehicle load across the tire's footprint. Camber is the tire's tilt inward (negative) or outward (positive) when viewed from the front and has significant impact on handling and shoulder wear. Caster is the angle of steering axis tilt when viewed from the side and while it does not affect wear, it does affect the vehicle's handling and tendency to track straight down the road. Toe is the direction that the tires are aimed when viewed from above. Toe-in is when the tires are pointed towards each other; toe-out is when the tires are pointed away from each other. Toe greatly affects tire wear since a setting just 1/16 of an inch off will make the tires want to travel sideways about 150 feet every mile.
The way you drive your vehicle - passively or aggressively - can greatly impact wear.