While driving the vehicle there is a groaning sound coming from the front end of the Tacoma from the front differential. There is a TSB from Toyota, but they only cover it under warranty and are not treating it as a recall. TSB # 0026-15. I think this is something that is causing wear to the front differential and could cause further damage/could lead to a crash if something was to lock up. The sound is consistent from 15-55 MPH no matter the driving.