How do I clean the gear box? - iRobot Roomba 560 Robotic Vacuum

By gear box do you mean the inside of Roomba or do you mean the latched brush section on the bottom? You can open the two latches and clean the brushes after taking them out. You can pop out the white/black ball wheel and clear the hair and thread that catches in there. You can unscrew the screw that holds the spinning white brushes and clear the stuff out of there. You can take out the filter compartment and remove all the screws to really clean that out. I started to open up the main compartment of Roomba to clean it out and stopped when it got more complicated. I know there's probably stuff in there, but so much gets caught on everywhere else that there's little left to get into the inner gearing, in my opinion.