Patrick,
I just had an axle seal go and it destroyed the left side wheel bearings. Had some damage on the end of the axle housing, so I had to take it to a machine shop to get repaired (used axle prices are much more than I thought!!). With 185k and since the axle had to be stripped down, I decided to have new bearings all around.
When it came time to reassemble, there was a jingling sound from the read end, while on the highway. After several disassembles and reassembles, here was the cause. The shim on the pinion when taken out was . 005. The jingling was the teeth not meshing quite far enough. It finally worked right with a . 045. Shop owner figured it was a size difference in the old and new bearing.
This being a small town and my wife's son working there, I only got charged labor for a standard axle rebuild. Otherwise I'd have a kidney up on EBay!
I have about 500 miles on it right now with no problems or noises. Going on my first road trip later this week. Hope it remains the same.