The pinion pilot bearing is the weakest link in Ford removable carrier rear axles. Failure occurs when either the bearing and/or casting around the bearing fails during a burst of power. This is an "N" case pilot bearing. Observe the absence of sufficient iron around the bearing. There's not enough to provide good pilot bearing support. The news gets worse for "WAR" and "C7AW" 9-inch cases, which have even less meat around this bearing.