"Adding this to the machine oil turns it into the ideal oil for use with large size machinery."
The Oil Additive (オイル添加剤 Oiru tenka-zai ) is a key item in Resident Evil 3: Nemesis.
As this item is the part of the Mixed Oil, it disappears from the inventory after mixing it with Machine Oil.
It can be found in the Umbrella office.
- BIOHAZARD 3 LAST ESCAPE OFFICIAL GUIDEBOOK. Famitsu. 1999.