Thanks for the suggestions. I am religious about maintaining vehicles with a good mechanic. In the case of my FEH, the 70k dealer service last week found all systems "good," including brake fluid, battery cold cranking amps, tire tread depth and tire wear pattern.

Actual brake measurements were:
Left front 7.80
Right front 7.60
Left rear 9.50
Right rear 8.80

The Ford multi-point inspection report card says "good" is "over 5mm or 7/32" (Disc) or Over 2mm or 3/32" (Drum.)"

I still suspect the brake master cyl. sensor, since that was the focus of the previously discussed service bulletin affecting my early production run '05. However, the service shop was unable to find a stored error code related to that issue.

This is my third winter in the FEH at the same Tahoe/coastal locations.