obd 2 is saying cylinder misfire 1-6 , and i just changed the plugs, any ideas, also how do i change the tranny fluid and is it good to pump it out or not? thank you

Check you spark plugs gap. E38 uses a special tranny fluid so make sure you use the right one. There is a drain plug on the side of the pan for draining. To fill you will need to pump it in until it overflows.