The invention relates to an oil pan (6) for an internal combustion engine transmission unit (1) comprising an oil pan housing (7) and a carrier flange, by way of which the oil pan housing is to be connected to the transmission housing (5) of the transmission. The carrier flange (4) is affixed to the transmission housing (5), and is connected to the oil pan housing (7) via a detachable connecting unit, wherein the connecting unit can be released or locked for the assembly and disassembly of the oil pan housing between the oil pan housing (7) and the carrier flange (9) regardless of the disassembly of the carrier flange from the transmission housing.