I don't see it ever being a problem. Even if our oil get's a little short, we could just top-up using the old ways.
Remember, before we discovered 'natural' oil, we just used to use 'whale oil'. Surely if natural oil ever did run out, we could just go back to getting our oil off the whales? Do dolphins have oil too that we could use? What other animals could we get our oil from? And how many whales do we need to slaughter to get enough gas to power a car for a year? All these are interesting questions. Possibly God invented whales for just this purpose? For powering our Automobiles? He certainly wouldn't want us Godly people walking everywhere!
If we start now, we could have our first few 'whale-farms' created out in the sea within the month, for whale breeding and extracting oil. Praise!