On the 14A and the leaf type gear leg, any rotation in the gear leg is nearly impossible. But lets not discount any of the wheels and its associated components (break) as the source of noise.
Would it be feasible to tow it with a car/truck with the engine off and some one that either walks along to observe where the noise is coming from?
As part of my first taxi, I had my wife drive along the taxi way (wide enough to do) and video the gear leg and engine for any abnormal movement.
And don't discount the gear leg(s) them selves being a source of noise, just because they are not round legs like on the most of the other RV models.