Autolocking hubs not locking
 

My '97 F350 4wd will not lock in. I looked under the truck to check hoses for a vacume leak. Mine does not lockby vacume. So someone told me to replace the actuater on the transfercase. Mine does not have that either.

This is what I have determined. The front drive pumpkin has no oil in it. Will that keep it from kicking in or just damage the gears?

If it is just the hub, can it be repaired or just have to be replaced?

if it is the hub, you can try cleaning it and regreasing it, but if that doesn't work i would suggest going with a set of manual locking hubs. with no oil in the pumpking there will definitely be some damage, but idk if it can be extensive enough to screw with the 4wd. the automatic hubs are always spinning around the axle, and when the axle itself starts to rotate, a gear on the hub is forced backward, locking the hub to the axle. so the only way your pumpkin could affect that is if the damage was so severe that the front axle no longer rotates with the driveshaft