Did my truck about a month ago (drain and fill, I put a drain plug in a while back). This is the 4rd drain and fill in 10,000 miles (I got the truck with 168,000 miles)
I had drained and changed filter and installed drain plug when I got it, drain and fill again 500 miles later, another drain and fill after 2000 miles, then this one.
I plan on a 10,000 mile drain and fill interval from now on.
First 2 were with Walmart Merc V, last 2 have been with Maxlife ATF.
I did my wife's Scion today for the first time at 30,000 miles, drain and fill using Maxlife ATF.
Plan on doing hers every 30,000 miles. It was a little dark coming out, but I read Toyota WS is a little dark to start off with.