While under hard acceleration, my truck started popping, and the check engine light was flashing. Pulled a P0300 multiple cylinder misfire code. After looking at some forums, I decided it was time to replace all the spark plug wires. Ford dealership wanted $38 per wire. O'reilly's auto was $73 for 8, a lifetime guarantee. I picked them up and installed the new wires. The truck runs better than ever. Shifting is better, holds gears longer.