Towing my 7800 lb. trailer up the grapevine here in Ca. the trans temp didn't even budge. Pulled the whole grade at 55+ even at the steep points. Engine was tacking as high as 5k for some decent periods of time but that's what gas motors need to do.
Mine was making noise also, and I found out that one of the screws backed out of the latch. You have to pull the plastic back just a little to see, but that's where I would look. It was driving me nuts!