6th Jun 2015, 23:26

There are two types of transmission "service" as far as I know. If your automatic has a problem already, a pressurized complete fluid flush can increase your problem, but a simple drain and new filter and good quality fluid put back in is a regular maintenance thing on some high mileage vehicles. That's going to leave about a third of the old fluid in it, so you may want to do just the fluid (not the filter) again after giving it time to blend.