When the trucks at work are low on oil, the drivers are asked to top them off. However, the oil fill caps are on extremely tight. One day, I asked maintenance for a rubber strap wrench. It worked, but it was a lot of effort just to pull the rubber strap through the cammed opening to form the exact diameter that would grab the oil cap. Fortunately, the caps have large ridges or knobs on them. Does anybody know a much better way, or tool, to get the oil fill cap off? Thank you!