Hello all, I recently developed a slow drip from my rear diff (8.4" out of a T100), not from the pinion seal but from behind the pinion nut. I pulled the nut off today to access and put RTV under the nut to stop the leak. The truck has 335K and I don't believe the rear diff has been rebuilt. I put a breaker bar on the pinion nut but it was not very tight, maybe 30 ftlb or so to loosen. There is not now or has been since I have owned the truck any pinion bearing play that I can discern. I tried to tighten the pinion nut up but the bearing preload increased to a concerning level and the pinion flange was hard to turn. I ended up putting the nut maybe 10* past the last spot it was staked and staking it again, and there is still no pinion play but I am concerned with the lack of pinion nut torque. I'm not an expert on diff setup but my understanding is that the crush sleeve takes serious torque to crush, and therefore there should be some torque on the pinion nut to hold things together without affecting pinion bearing preload. The FSM refers to the preload but I have no way of measuring this without the diff on the bench, it also only mentions that the pinion nut torque should be under 333 ft lbs. Thoughts?
