There is a trany vent located on the top of the transmission in the Nitro. If there was enough heat expansion, I suppose you could develop a drip. In the case of the Blazer the vent was plugged from wheeling, and the pressure buildup inside would cause trany fluid to burp out the filler neck and then drip onto the exhaust. More @Wikipedia
Hover over any link to get a description of the article. Please note that search keywords are sometimes hidden within the full article and don't appear in the description or title.