IT may be play in the shifter linkage (assuming it is not a otop shift case). If so, that could mean that the linkage tries to push into 4WD but can't quite make it (enough for the light to come on but not enough for the gears to mesh). Check the linkage under the truck:
[Linked Image]

r.c.brown@ieee.org
TruckEditor@tlca.org
Project: 4Crawler
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