Rear end seems to be "holding up" after I stop and then start out again. on 2005 Nissan Xterra

When I come to a stop at times, my 05 Xterra's rear end seems to hold up, as if I am towing something heavy. I hit the gas and my RPMs and engine rev but it is as if something is holding back on the rear end. It does not do it all the time, and if I hit the gas and then let off of the gas it seems to "kick out" and is fine.

Asked by for the 2005 Nissan Xterra
Have ALL rear brakes checked for binding, including the park brake 'shoes' behind the rotors.