DIY on changing the transmission fluid in a Lexus ES or Toyota Camry V6.
Procedure is the same for the Toyota Camry, Solara, Avalon, Sienna and Lexus ES300 as well as Corolla, Yaris, Matrix, Highlander, RX300, RX330.
Its recommended to change the fluid every 15-30,000 miles or every other year to prolong the life of the transmission components.
This procedure illustrates a drain and fill of the transmission pan, which replaces 1/3 of the fluid in the transmission. To replace all 12 quarts, drain and refill the transmission three times over a short period of miles.
A transmission flush is possible via the cooler lines but is not recommended due to the potential for small metal particles to a fix to the innards causing blockages.