when i drive it makes grinding noise but doesnt seem to slow down or anything and mostly does it while accelarating. also when i try to put it in 4wd it will grind when the transfer case is in nuetral and when its in 4wd the light doesnt comeon anymore and the tires wont spin but the front driveshaft does?

 

4x4 actuator might be sticking causing it to grind since the front end parts ALWAYS move that could be what your hearing