I want to thank everyone, the bits and pieces of information are really helpful. Such as with Nick-B's post I now know that with a torque converter drain plug I don't have to take my RV into a oil change facility to change out the AT fluid. I will also look into that second transmission cooler. Back in 1990 my non-mechanical brother took a 10,000 mile RV trip in a second-hand Class C RV that had no transmission cooler at all. Needless to say, half-ways through the trip he had to replace his transmission. I don't care when the RV was built, the cheapskate manufacturer should be flogged for leaving off such an important piece of equipment.
Steve