Do I need a transmission flush at 57K miles if 07 Yaris should last until 100k?

[lejulie]

Hi!

I don't know much about cars but I am learning a lot from this site! I have a 2007 Yaris with 57,000 miles. I took it in and the mechanic said that the transmission fluid was dirty/burnt and recommended getting the following transmission flushed:

transmission flush (std): complete BG chemical flush with a detergent and neutralizing agent added to new transmission fluid to clean the entire system.

-Dexron III ATF, 16 - $79.84
-BG Trans Flush Kit - $33.55
-Disp fee - $1.00
-Labor - $50.56

Total: $164.95

The transmission fluid has never been changed since 2007. I thought with 2007 Yaris' that the ATF didn't need to be changed for 100,000 miles. Should I go ahead and get the ATF flushed now (or drained and filled?) or wait until 100K like it says here: http://www.yarisworld.com/forums/showthread.php?t=13968

Lastly, what is Genuine Toyota ATF-WS? Is it Dexron III ATF? Or can you only buy Genuine Toyota ATF-WS at a Toyota dealer?

Thanks so much!!
Julie