How well the rear suspension controls the position of the rearend is the most critical issue that determines how much pinion angle will be needed. Some types of rear suspensions offer more control than others and require different angles. a ladder-bar suspension normally requires ½ degree of pinion angle, a four-link requires 1-2½ degrees, and a leaf-spring suspension requires up to 6 to 7 degrees. In all examples, we’re talking about negative pinion angle, i.e., the pinion is nose-down in relation to the driveshaft.