I have a 2004 , 5.4 with 249,000 or so miles. My issue is the fuel gauge/fuel pump. Not sure. If I fill my tank the gauge will show only 3/4 full. But if sweep the gauges the gauge goes full swing just slower than all the other gauges. Plus my I have an intermittent brake light that also comes on from time too time. I was wondering if the fuel pump has anything to do with the gauge issue. Or maybe replace my instrument cluster. Truck starts and runs good for high mileage.

ED

 

sounds like the cluster is going batty... brake light is the sign

 

Sometimes......it's a good idea to check the battery to make sure it is fully charged.....and check for corrosion.

Scotty Kilmer had a video about this: many times the battery has to be in tip top shape to deliver all the juice neccessary for new vehicles with such a high power draw through all those modules.

No kidding......recharge the battery first....see where it's at.....then check for corrosion on the ground or batt terminals.