First check would be the CV axles. Turn your wheels all the way one direction, get out and look behind the tire. More specifically the rubber boot on the axle, are there any rips/tears?
Check both sides. Any rip/tears and the CV axle will need to be replaced.
Next check, look under the truck at the front driveshaft where it connects to the transfercase. Any rips/tears in that rubber boot? Is there a "grease ring" just above the connection of driveshaft/transfercase? If so, the driveshaft will need to be replaced as a whole. If you need one PM a member on here by the name of ericautopart (
CLICK ME TO DO SO), he has them for a discount to forum members.
If both of these check out, it is possible that the wheel hubs/bearings may need to be replaced.
Jack the truck up, put it on jackstands for safety, grab the tire at the 3 and 9 O'clock positions and feel for any play. Try again at the 6 and 12 O'clock positions. If you feel any play whatsoever, replace the wheelhub/bearing ASAP.
If everything checked out, let us know.