Now that I'm back home and in front of my computer, I can explain what happened:
Let me preface this by saying that i am a relatively experienced wrench-turner and fabricator; I grew up on a farm, spent almost 9 years in the Navy as a nuclear ET, and have built dozens of off-road rigs. I'm also the assistant chief on my local fire department, and besides being a driver for all of our vehicles I also do most of the maintenance and repairs on them. I am good at finding problems with components WELL before they turn into something serious. Many of my friends laugh at my obsessive need to PM my vehicles, tools, and equipment.
But...I screwed up with my deuce.
Last March and April, I took the deuce through a series of water crossings and mud bogs. Following that, I drove it through the seasonal floods on hwy 101 just south of Seaside. I recently drained/refilled the gear oil in the axles, tranny, and tcase because I was worried about water in the oil. I also felt for excessive play in the wheel bearings when I had it up in the air (there was none). I did NOT pull the hubs and check for water/mud/sand in the wheel bearings. I also did not check the hub temperature on this trip (both the bearing grease and temp is something that I do religiously when I have a trailer on the road). This turned out to be a BIG deal.
I was driving up I-205 in heavy traffic. I did not detect any kind of abnormal noise, smell, vibration etc. During a slowdown in the traffic the brakes felt abnormally "spongy," although they still worked. I made a split second decision to get off at the West Linn exit, instead of driving the remaining 6 miles to my destination. When I pulled into the Les Schwab parking lot, I noticed a small amount of smoke and a hot grease smell coming from the right front wheel; after a quick inspection, I realized that I could actually see the entire brake lining; the hub/drum was almost 4" away from the backing plate. When I jacked it up, the wheel literally fell off. I could have easily lost the wheel at 55 on the freeway; especially had I not stopped to investigate the brake symptom. The only thing keeping the wheel attached was luck. The race on the outer bearing had gotten so hot that it welded itself to the spindle. The cage came apart, and allowed the hub and drum to work itself off of the spindle. The reason the brakes felt spongy is that the shoes were outside of the drum and had nothing to press against. After repairing the passenger side, I took apart the driver side and found the bearings to be in rough shape (although with some new grease, good enough to get me back home).
I dodged a major bullet. As a firefighter/EMT I'm well aware of the carnage I could have caused...I feel pretty lucky. This incident cost me a few $$ and that is about it.
Lessons I took away from this; wheel bearings on the Rockwells are a critical part to inspect; especially after a water crossing. And, hub/tire temps should be checked at each stop. And, in a vehicle as noisy as an M35A2, you may not notice a problem until it is too late.
The last thing I want to do is shed a negative light on the MV community, on my fire department, or my business. I almost did just that yesterday...I can say for SURE that I will be more cautious in the future.