Problem solved (for now) by pumping in more fluid. When I cracked the fill plug, nothing came out (though the plug opening is too small to reach up in there and check it with a finger).

We'll see if the problem is really gone, or if it comes back, but all appears to be well.

Thanks to all for talking me off the ledge. Common sense triumphs again.

-Joel
'02 Trooper S
The dog-mobile.

'90 Trooper LS
Dearly departed after 13 years in the family. Donated to WAMU Radio in DC.