It is possible to take the Mako through the gap in between the two rocks, where you are supposed to get out and travel on foot. Drive in to the gap, then from inside the gap drive up the left rock, until you are completely on your side, wedged between both rocks. Slowly inch forward and use boosts to slide through the gap. The geth and the walkers (the mini boss fight after the video) will not attack the Mako, and they die after only a couple of cannon shots.