Haven't heard of any problems.... you did shut the motor off when you
refueled, right?

I have found a couple of tsb's which will probably fix the issue with your
vehicle.

Make:  FORD  
Model:  EXPLORER  
Year:  2004  
Service Bulletin Number:  17494  
NHTSA Item Number:  10007334  
Summary Description:    
DISTANCE TO EMPTY NOT DISPLAYED. *TT  

Make:  FORD  
Model:  EXPLORER  
Year:  2004  
Service Bulletin Number:  17316  
NHTSA Item Number:  10008166  
Summary Description:    
FUEL SIGNAL TO INSTRUMENT CLUSTER SERVICE TIP. *TT  

Just bring these two tsb's to your dealer, explain the problem that you're
having with your vehicle, and give them the tsb's.  Good luck and let us
know how the repairs go.

I recently had this problem with my 2003 XLT. I filled up and the gas gauge
didn't go up at all. I went back to the station explaining that to them
figuring I hadn't really been pumping gas in. I said I was going to try
another pump there and actually put $3 more in but that was it. On the 35
min. drive home later that day I watched the gauge slowly climb to full.
That was 3 weeks ago and I haven't seen the problem again and hope I never
do.