2004 Ford Explorer Noise coming from back passenger side

I have recently noticed a clicking noise come from the back passenger side of my car. It only happens between 11 and 13 miles per hour when I slow down gradually. It happens wheather I have my foot on the brake or not but if I stop fast it does not happen. The speed of the clicking coinsides with the rotation of my wheel. I feel nothing inside. The ride and handling is great. I don't even hear it unless one of my passenger side windows are down.

Thanks,
Dan