4x4 or front hub noises

Auto hubs or manual?

Typically noises like that are a result of the hubs no completely disengaging. That could be a vacuum leak within the integrated wheel end (IWE) system.

look at the iwe actuator on both sides for corrosion. pull the vacuum line off and use a vacuum tool on the bigger of the two metal tubes coming off the actuator. pull a vacuum on the actuator and see if it hold a vacuum. if it leaks you need an actuator. if not then you need to inspect the rest of the system. just make sure that you flush the lines with air before installing a new actuator. also check the two check valves in the vacuum lines to see if they are working.