I am not familiar at all with the manual xterra, but what about a throw out bearing ? Had a subaru that acted like that once when the bearing was going out on it. Just a though.
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2002 SE/SC R.I.P. March 2015
Bielstien's
Shrock Sliders
Reman'd engine installed 5/16/09 at 87,894 miles

Captain 38-90
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