Stoped at an R.V. park and let out the living/dinning room. When the slide was out, heard a "bang". Checked under the unit to see if something was broken, nothing looked wrong. Tried to bring in the slide unit , the motor ran but the slide unit did not move. Took the motor and gear box apart and saw that the worm gears had four teeth broken off. Any one have any idea what would cause that? Ordered new gear unit from Barker but is has not arrived yet. Any ideas would be appreciated.