RobbieH,
If the actual gear(s) are slipping, it should be pretty obvious once its completely extended or retracted. Either each corner wont be fully snug against the exterior of the coach when fully retracted, or each corner wont be fully extended at full extension. To check full extension, I just measured the distance of each corner to the coach and make sure they are all the same. I think that each time the gear slips a tooth, it equals approximately 3/16 of slide distance. So it will be obvious if any have slipped.
