So there is agreement in flushing the transmission, should it be necessary- BUT the pan has to be dropped and the internal filter cleaned really well or replaced. This is a must be done step.

I had my transmission rebuilt about three years past b/c the fluid was like a brown milkshake and even with the filter change it needed rebuiilding. There is a lot more to the story but this is the short version.

The ecectronic solenoids are dificult to find-(in China, since no dealers were able to get them or have them in "stock")
also the radiator may have to be changed if the fluid is polluted. The torque converted has to be cleaned out as well.
Maybe you wont have to do all this- but just FYI.