stumbing

Am having a problem with my truck stumbling at about 1500rpm. Have new Ac plugs gapped at .60, new fuel filter/pcv valve. Have had emmision service done. put a can of BG 44K in and the truck seemed to do fine on the highway. Put 330 miles and got 17 MPG. Could the problem be the plug wire or something different. No SES at present comes and goes.

It could verry well be your plug wires if you did not change them ESPECIALLY with the .60 gap. I had a verry similar problem a few months back i suggest reading on this thread , particularly post #13 and 15 http://www.automotiveforums.com/vbulletin/showthread.php?t=314632&highlight=rough+idle