georgie,mine has that exact same 1st to 2nd shift.I call it the power glide shift(GM`s old two speed trannies shifted that way)unless they were altered.Any way,it is most pronounced when cold.I notice a better shift now that I`m using the Wolf`s Head full Synthetic.But it`s still their (and kills the off the line performance) of the vehicle.Not that the RX is a fast car,but some times you need that extra umph off the line.

 

toyota dealer said they use 13 quarts to do a complete flush on RX330.