Q: My SUV is making a grinding noise

Yesterday, I noticed that there is a slight grinding or metal on metal rubbing sound. The sound is not constant, it seems to happen when accelerating from a stop and/or low speed, and then it's gone. It does not get louder or change pitch with increased speed. I hear it around 25 MPH and that's all. I don't hear it when driving highway speeds. It seems to be coming from below the center console or dash area. I don't notice it if I drive and keep the car in only electric, and when I switch gears manually I don't really notice it either, which to me rules out transmission. I hear the sound in both Auto 4WD and 2WD. I have checked the transmission fluid and everything seems fine. My only thought right now are that it is either a hub bearing or something in the front differential. I haven't lifted it up the truck check the wheels yet. Any suggestions?