My friends 2000(I think) explorer With the 4.0 86k has burnt up two pumps in two weeks. this last one only lasted a day. There was over half a tank of fuel in it when installed and only drove it to work and back, about 50 miles. Next morning he went to leave, nothin. Pump won't run. Checked fuses and relays they were okay.

Why would this be happening?

 

just confirmed it's a 96

 

If there is a restriction in the fuel system (such as a plugged fuel filter) it could cause the pumps to fail prematurely. I would be surprised to find that one would fail within such a short time though. It may be time to make sure the power and grounds to the pump are clean and not corroded anywhere.

-Rod