The gearbox for the four main gears on my PDC 18/4 is difficult to change. I have to use two hands to get it to change gears in some cases. Has anyone dissembled the front and cleaned/re-lubricated it? I called in to festool, and they basically said to just mail it in and they would quote me a repair cost. I'm pretty sure they are just going to add some grease, and clean it up. Any idea what they would charge for something like that? I kind of don't want to pay to ship it over and also be without the tool for a few weeks, especially if this simple maintenance could be done on my own. What are your thoughts? Should I just unscrew it and dig in?