Mine was flushed at 30k miles and at 60k miles. Now has 92k miles and haven't flushed it since. I'm thinking about having it done at 100k. The 30k mile flush was done under warranty because it was required to be maintenanced at 30k and they did a number of things, this being one. The shifts my trans makes are very smooth, can't even feel the 4-5 shift. Just my 2 cents