There is no vacuum connection to the tranny.

If it's a coolant leak, the exhaust smell will be sweet. If it's atf, it smells like atf spilled on the hot exhaust manifold (ASL a fried a/t). Dunno what fried synth smells like. Coolant level drops? Any hard first of the morning cranking (hydrolock)? Any chocolate yoohoo in the oil pan? Any funny smells out of the radiator?

Not responsible for advice not taken...