Bolts attaching transmission fluid pan to the transmission should be torqued to 8 Nm (6 ft/lbs). It's possible that your pan is deformed from previous over-torqued bolts in an attempt to stop the leaking. The pan gasket and properly torqued bolts provide a tight seal. Best to remove the pan and check the condition of the flange surface with a straight edge. Adjust, as required, so the flange is perfectly flat and will provide a tight, unifrom seal when the pan is installed.

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Fred Hoelzle