another 4x4 problem

[yfzrunner]

This is my dads truck but he had problems with 4x4 first with the stock hubs it would not lock into 4x4 with the buttons or by hand with the hubs. So he replace the factory hubs with manual warn hubs and now all it will do is make a loud popping sound and still wont lock into 4x4. Any input on this some say a sticky solnoid in the front diff. When you turn it to 4x4 low or high the transmission goes into 4x4 but wheels do not. Maybe he is not doing it right but i believe he put in in n then turns the knob and the hubs by hand.

[F350Powerstroker]

There is no solenoid in the front diff pretty sure that's a soccer mom IFS Chevy thing... The factory hubs auto lock through a vacuum system. Seeing as you have warn hubs now that does not come into play anymore. (Good move by the way those auto lockers are POS) Now is the noise coming from your transfer case when you flip the switch or the axle itself? Turn the front drive shaft see if it is engaging properly. Also check your hub bearings if they are in super poor condition sometimes your auto lockers won't engage. I have seen it happen.

[yfzrunner]

i believe its the hubs them self making the noise. so locking up the hubs do we even still need to put it in 4 wheel drive in the cab i believe just for the transmission im going to meet dad at the deer lease and i will mess with it and make sure were the noise is coming from.