Four-wheel-drive won’t go into four-wheel-drive?

The four-wheel-drive light says it’s in four-wheel-drive. I can hear it click like it’s going into four-wheel-drive. I can put it in four wheel low The light will come on and I can hear click a lot louder, but it will not go into four-wheel-drive. I’ve checked the vacuum everything seems to be good. It’s gonna change the motor to the transfer case but I’m waiting on the answer. Thanks for everything. i’ve also changed the actuators on both wheels.