I did a drain and fill with Amsoil Signature Series fluid today at 16,438 miles, along with an oil change as well. It is a very easy procedure and I refilled through the dipstick. I took some pictures of the procedure as it may assist anyone who is about to attempt it. Around 3-3/4 quarts were drained out and replaced. The drain plug was covered with metallic shavings and some grimy sludge as expected, but not too bad.