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| Tire Wear Patterns |
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Worn on:
Outside edges: tires that are worn on the outside edges have been under
inflated. There is excessive contact with the outer edges of the tire and the road
surface as the vehicle travels down the road.
Center of tire: tires that are worn in the center have been over inflated. There is
excessive contact with the center of the tire and the road surface. Always use a tire
gauge when inflating tires.
One of the edges: when the tire is worn on one side but not the other the camber
angle is off either negative or positive. Positive camber is when the top of the tire
leans away from the vehicle. Negative camber is when the top of the tire leans in
towards the vehicle. This can also be caused by bent or damaged front end parts:
tie rods, ball joints, etc.
Tire is feathered: when the tire is feathered across the tread the tie rods are worn
or the vehicle needs to be aligned. The ball studs get loose in their sockets
allowing the tires to toe in/out as the vehicle travels down the road. Toe in is when
the fronts of the tires are closer together than the rears and toe out is when the
fronts of the tires are further apart than the rears.
Tire is scalloped: when the tire is scalloped or cupped across the tread it is
usually caused by bad shocks or struts. This can also be caused by out of balance
tires. Jounce the front end to see if it oscillates and test drive the vehicle to see if it
floats and leans excessively around corners. Bad struts are the number one cause
of cupped tires.
Tire wear can indicate a worn steering or suspension component, an over or under
inflated tire, or a mis-aligned vehicle. Visual inspection of vehicle tires is an
important step in the preliminary inspection process.
Outside edges: tires that are worn on the outside edges have been under
inflated. There is excessive contact with the outer edges of the tire and the road
surface as the vehicle travels down the road.
Center of tire: tires that are worn in the center have been over inflated. There is
excessive contact with the center of the tire and the road surface. Always use a tire
gauge when inflating tires.
One of the edges: when the tire is worn on one side but not the other the camber
angle is off either negative or positive. Positive camber is when the top of the tire
leans away from the vehicle. Negative camber is when the top of the tire leans in
towards the vehicle. This can also be caused by bent or damaged front end parts:
tie rods, ball joints, etc.
Tire is feathered: when the tire is feathered across the tread the tie rods are worn
or the vehicle needs to be aligned. The ball studs get loose in their sockets
allowing the tires to toe in/out as the vehicle travels down the road. Toe in is when
the fronts of the tires are closer together than the rears and toe out is when the
fronts of the tires are further apart than the rears.
Tire is scalloped: when the tire is scalloped or cupped across the tread it is
usually caused by bad shocks or struts. This can also be caused by out of balance
tires. Jounce the front end to see if it oscillates and test drive the vehicle to see if it
floats and leans excessively around corners. Bad struts are the number one cause
of cupped tires.
Tire wear can indicate a worn steering or suspension component, an over or under
inflated tire, or a mis-aligned vehicle. Visual inspection of vehicle tires is an
important step in the preliminary inspection process.