What's the condition of the fluid on the dipstick? Unless it's dark, gritty, or has a burned odor, leave well enough alone. Since it's impossible to get all the old fluid out because there's no way to drain the torque converter, stirring up things by dropping the pan and doing a filter swap doesn't accomplish much. The only thing "flushing" does is flush some of your money down the drain, and it could cause other problems.
Jerry
