99 Expedition 4x4 clicking noise in wheels

[Z28injectedSS]

Hello, i have a '99 Expedition 4x4 (140,000) that makes a clicking/ratcheting sound in the front wheels. The sound goes w/the speed of the truck (slow speed- slow click's & fast speed- fast click's). I jacked the truck up & spun the wheels & it doesn't make the sound (only when wheels are on the ground). There is no play/wiggle in the front tire when jacked up. I did a search on here & everything I found points to a vacuum leak or faulty solenoid not allowing 4x4 to completely disengage, but I don't believe this truck has that solenoid (can't locate it in the engine bay). Any help & suggestions would be greatly appreciated. Thanks for your time.

 

[Z28injectedSS]

I took the front wheels off, looked around & didn't find any abnormalities. Put them back on/torqued them down & now the clicking is gone. I guess the lugs had backed off causing the click? Anyway happy it's not making that noise anymore (it was driving me crazy). If anyone's experiencing the same symptoms, you may want to try tightening the lugs 1st. Thanks.