This tip is the most important aspect of completing automobile repairs when you are working alone. If you need to elevate the vehicle with a jack, use a minimum of two, locking jacks to hold the vehicle in place. If you use a floor jack, ensure that the bar will not pose a tripping hazard. Once you have raised the vehicle to an appropriate height and installed the locking jacks, attempt to shake the vehicle. While this sounds counterproductive in the event of a fall, it will test the stability of the raised vehicle. If the vehicle remains stable, you can proceed with the wheel bearing, hub, or other repair you intend to make beneath the vehicle.