Fuel tank Problems

Ive got a ford F-150 1988 duel tanks 4x4. The problem is that when running fuel out of the front tank it will pump fuel into the back tank. And when it runs on the back tank it pumps fuel into the front tank. The truck runs fine and starts well, its just those fuel tanks. Does it hurt to run it like this??? And what needs to be done to correct it???

hi ford trucks had a recall on alot of there models due to one tank pushing gas into the other tank what caused this is on each fuel pump in each tank there is a pressure check valve that keeps one or the other tank from pushing fuel into the other what i mean is on each fuel pump is a valve and once you switch from say the rear tank to the front the valve on the pump will not allow fuel to go from one tank to another this is the reason for had a call back on them the only thing i could say is replace the fuel pumps or drive it like it is its just you got to whatch and make sure the one pump or other doesnt over flow the other