Used this tool a few times already to service a power transfer unit and rear differential. My vehicle does not have drain plugs for these gear boxes (only fill plugs) and the manufacturer claims the fluid inside is filled for life. There are many documented cases of mechanical failure due to lack of maintenance with this particular set up so i decided to purchase a fluid evacuator to facilitate some sort of maintenance. This one was not the cheapest one available but i figure i have already covered the cost with the number of jobs i have done with it. I do have the luxury of being able to hook up to shop air so i have been quite satisfied with its performance.