Transmission fluid change or flush

I just bought a used corolla 2010 CE (automatic) a month ago with 200K kms on it. During the inspection recently, mechanic advised me for a Transmission fluid flush (he said it is very darkened in color) and coolant flush. I just read a bit about flush and people are suggesting not to do it. I have driven vehicle for about 200 kms now and it is working just fine, I don't feel any problem (but I am a new driver, don't know much about vehicles). So, should I go for a transmission fluid flush or just change it?

And what about the coolant flush?

Any suggestion would be highly appreciated.



I Love Corolla's!
I don't recommend doing a transmission flush but instead, do a drain and fill. This way, you drain the old fluid that's in the drain pan and then after driving another 100 kilometers or so, do another to clean out the remaining fluid (not all of the fluid will be in the drain pan at once which is why you have to do this more than once). A transmission fluid flush will put too much force and may damage the internals of the transmission. I did 3 drain and fills on my 2011 auto this past summer and the fluid went from black to red and now I change it every 2 years. A coolant flush would be good to do at this point as well.