All kinds of tractors in the use of such and such failure often happen, and some serious consequences of a failure, cause personnel casualties and property losses. If we can found potential problems in a timely manner, can avoid unnecessary loss. Before the tractor failure tend to show the unique appearance of the phenomenon, this can also be referred to as precursors. These precursors are generally have to hear, audible and visible and touchable or measurable properties, tractor driver can be judged through the following several aspects locomotive technical conditions: a, instrument exception when the driving of the tractor should form the good habit of often watch instrument, timely find problems from the locomotive instrument. This is because the instrument can indicate the condition of various operating parameters, through which can ? machinist