All good thoughts and thanks for the replies.
The post several years ago might have been mine on a different Ranger forum. It got NO responses!
I'll waterproof the coil for good measure even though driving in the rain of all intensities is not a problem.
Both battery cables are good at both ends.
The problem happens in both 2WD and 4WD.
Don't know if it occurs while idling, i'm usually moving.
Problem occurred with my old tires and also with the new set put on in Oct. 2009. Always 4 of the same kind and regularly rotated.
Another "expert" thought the cause might be the Mass Air Flow sensor in need of cleaning. I just finished doing that with MAF cleaner, but won't know if it will solve the problem until the snow flies. There were no other signs of engine malfunction which would point to the MAF.
Still boggles the mind.

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David in ski country Vermont
2002 XLT, 4wd, 4.0L, manual, 70K