I just bought a 1978 GMC K15 with a 454 7.4l big block that was swapped into the truck out of a camper. Has a np203 transfer case and a turbo 350 tranny. The motor runs but when you put the truck into drive it does not move, so vehicle runs but DOES NOT move. Any suggestions as to what it could be? thanks

 

Trans transfercase linkage cable tconverter drive shaft
the list goes on and on

 

Make sure the transfer case is not in neutral. Put it in gear, any gear even reverse see it mthat does it.