The proper height of a snowblower depends on the type of snow and driveway conditions you’re facing. The snowblower should be set between 0.75 and 2 inches if you have a gravel driveway.
When unsure about the proper height, think of it this way: a snow blower can deal with powdery snow even from a great height. Otherwise, it should be as low as possible without touching hard surfaces on the ground.