[das2123]

Fluid on your driveway means it was leaking. From where, I can't answer. If you are doing a drain and refill,it would only take about 3-4 quarts. Doing a tranny swap, he probably drained the torque converter as well which holds about 3-4 quarts as well. Hope you had a warranty on the transmission. Ask your mechanic what type of fluid did he put in there?