Big puddles on driveway?
Does it do this running? If so check the cooler, it could be plugged and not allowing the fluid to flow and so it is overheating. If it just runs out just sitting there then it could be a broken pan gasket or seal, a cracked transmission case, a front pump seal could also be bad but it would only leak while running but it can pool up in the bell housing so even sitting it can still be dripping. HTH
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