Board Thread:R2D - General Discussion/@comment-26356237-20150514002424

Your van runs on oil. You can use your van for 2 minutes or so before it runs out of oil. The lower gas you have the slower you van goes. If your van runs out of oil then you must either find oil (which is randomaly scattered around the map) or buy it from the menu store for $50 or so.

In order to buy oil from the menu store you need to buy an oil can for $2,000 or so.  