Where there's Smoke there's Fire
Brother of The Benz, Klasse
If your tranny is smoking from within, you have major problems.
But in the real world it would most likely be an oil leak contacting the exhaust system.
When you stop, the smoke rises from the mid section of the chassis, where the tranny, the cat/conv and mid-muffler reside.
Don't through the Baby out with the wash, check it out.
Happy Trails Beep Beep from The Spiderman in Houston!!!