Is my 4WD engaging?1991 F150 5 spd?

I just bought a 1991 F150 4X4 5 speed trans. Auto hubs stick 4X4. When i shift into 4hi or 4lo the light comes on but there is no noise what so ever. is this normal or is it the hubs? I also tried to test it but can't really tell if the front wheels are turning or not. When i did put it in 4lo you could tell the tcase was working.