Cylinder wear is a common issue that affects many engines, and it can be caused by normal use as well as improper maintenance. Cylinder wear occurs when the cylinder walls become thin and worn over time, resulting in decreased efficiency and power output. Acceptable cylinder wear is considered to be up to 0.003 inches of clearance between the piston rings and the cylinder wall. Anything greater than this amount will typically lead to more severe engine problems such as excessive oil consumption or even complete engine failure if left unchecked for too long. Regular oil changes, proper lubrication, diligent inspections of your cylinders, as well as regularly replacing worn parts are all key components in keeping acceptable levels of cylinder wear at bay on your vehicle's engine.