What angle should the pushrod and slack adjuster make in the released position?

Answer: C — Greater than 90 degrees

The access to proper brake release comes from how the pushrod sits relative to the slack adjuster when no air is applied. In the released position, the pushrod should form an obtuse angle with the slack adjuster — greater than 90 degrees. This orientation keeps the pushrod from staying in contact with the slack adjuster and allows the mechanism to return fully to rest, preventing brake drag after release. If the angle were 90 degrees or smaller, the pushrod could remain against the adjuster or bind slightly, causing partial braking or slow release. An angle near 180 degrees isn’t how the linkage sits in normal mounting, so the practical, correct condition is an angle greater than 90 degrees.