1996 GMC Sierra ELECTRONIC 4X4 SHIFTING

There is an electric device called the 4 wheel actuator motor on your transfer case. This is the thing that transfers your truck to and from 4 wheel drive. The connection may be loose or the ground may be loose or corroded. These motors also fail sometimes. There is also a similar device that locks your hubs in and out automaticaly, located on the front differential. It also may be the switch itself, these commonly fail. Keep me posted