Paranoia: a mental condition characterized by delusions, suspicion, and mistrust.
This is what happens when you take your vehicle to a mechanic to fix a problem.
My mechanic, whom I have known for many years and completely trust, just called me. he said, specifically, "we can't find anything wrong".
The first rear differential failure was, without question, a failure. Loud bang, followed by the rear end locking up and lots of grinding and angry noise.
After the repair my daughter was driving the truck and came to a red stoplight. As she applied the break she could "feel" something wrong and could hear some "groaning". She questioned if she was simply paranoid due to the previous failure. She continued on the green light until the next red stop light. Again she applied the break, and could feel the the truck doing something wrong, accompanied by some groaning. She then pulled over and called me.
When I arrived, I got in the truck and started it. It sounded normal. I put it in revers (like I did the first time) and let off the break. The truck idled into reverse and slowly moved normally. I then put it in Drive. No bad noise. I then let off the break -- the truck did NOT idle forward. I slowly applied some throttle and the truck "groaned" and struggled to move forward. I immediately let off the throttle, and put the vehicle in Park thinking the rear-end was again toast.
My mechanic is thinking that we simply had the emergency break on. We typically do not use the e-break (automatic transmission). My daughter doesn't recall setting it either. I certainly did not check it. But, regardless, the mechanic said that the truck is driving around just fine. He even power brake'd it and did a small burn-out just to put some load on it.
I'm relieved, embarrassed, and a little skeptical right now. But I'm also hopeful that things are all good.