2-transmission oil
you didnt ask for other oils. there is transmission, that if you own a manual transmission, you are lucky, because it only takes some 4 liters, and, according to the manual, it is very close to the engine specifications. to the point that you could use exactly the same. and if you got a car without record, you have no idea when (or if) was it replaced. i got mine in wonderful appearance condition, but previous owners didnt do a thing so i decided to check it: it was BLACK!, so i replaced it (mine had about 65,000 miles).

but if your car is an automatic, replacing the oil is another story. if you want to replace all the oil is expensive. it can not be drained fully, and would take replacing it 3 times. and is about 8 liters of full synthetic that costs about 3 times of regular. ask the experts.