One wheel turning is sort of a good sign. It means you are getting power and torque to the front end, which means the transfer case and hub locks work. It also means yo don't have a locker up there. Remember, a Jeep in 4wd without lockers is really a two wheel drive....one wheel in fron and one wheel in back. Add lockers front and rear, and then you get true 4wd.
I put Eaton elockers in mine front and rear...and the JEEPS CAPABILITIES INCREASED TREMENDOUSLY.