Engine crankcase

An engine crankcase and transmission assembly includes a transmission housing including a forward mounting portion and a crankcase including a rear-mounting portion configured for mounting to the transmission. The rear-mounting portion of the crankcase includes an upper section and a lower section spaced apart from the upper section so that the first transmission housing and the crankcase define a passage there between when mounted. An oil sump at a lower portion of the crankcase including an expanded section with an outer surface extending rearward beyond the rear mounting portion of the crankcase. An adapter provides for mounting to a second transmission housing. The crankcase receives interchangeable first and second oil routing devices with oil line fittings for receiving complementary oil lines. The first oil routing device includes first oil line fittings for receiving first oil lines extending toward oil fittings on the first transmission housing, and second oil routing device includes oil line fittings for receiving second oil lines extending toward oil fittings on the second transmission housing.