Here's a breakdown:
* Oil Pan: This is a metal part that holds the engine oil.
* Transmission: This is the gearbox that transfers power from the engine to the wheels.
* Flexplate (or Flywheel): This is a metal disc attached to the crankshaft (inside the engine) that allows the transmission to engage. It's bolted to the transmission.
Therefore, there's no need for a gasket or flange between the oil pan and transmission.
If you're experiencing a leak in that area, it's likely a leak from the transmission itself, the oil pan gasket, or the flexplate bolts.
Please be careful when working on your vehicle and consult a mechanic if you're unsure about any repairs.