I've just had some maintenance done and am planning on what else needs to be done, and have been considering the pros and cons of having the work done manually vs with some kind of machine. It seems that for brake fluid, using a machine that simultaneously adds fluid while removing old fluid from all 4 wheels is the superior method. If operated correctly (which should not be hard to do due to the change in fluid color being very visible), it would seem to be certain of exchanging all the fluid and minimizing the chance of adding air or moisture during the procedure. What are your thoughts on this? For ATF, I think a machine would be useful only if the pan was dropped as well and the technician made a point to cycle the transmission while the fluid was being exchanged. I also read that running the machine through the pump inlet, with the pan and filter removed, was more desirable. For power steering, the benefit of any machine would be to prevent the chances of air getting into the system, otherwise a manual process would seem to give as complete a fluid exchange. For coolant, I haven't looked into this much. I presume there is a chance that a machine could perform a more thorough clean by using more pressure but is there a chance of unsettling / loosening crud that you don't get out but which causes problems elsewhere afterwards. Be great to get peoples opinions on the best way for each of these changes. I know that I could do many of these things myself, but I'm firstly interested in whether a machine could be a superior way of doing any of them.