What could be wrong with my transmission if its leaking
Either the transmission lower pan, or one of the hoses is leaking. In some cases, the leak is in the radiator, where the trans cooler resides and the coolant and transmission fluid mix. Fix the leak once you find it ASAP, you don't want the trans to run low on fluid.
Where is the puddle after parking? If around the front wheel on the drivers side it's leaking near the radiator, maybe the two fittings. Look under the vehicle. If the bottom portion of the engine has oil from the fan backward, suspect the radiator fittings or the line or the radiator itself.
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