I used to have a 98 F150. Right before I traded it off, the heater core went out. I got on here and read about the issue after it was too late to do anything about it. Do the 2004 - 2008 F150s have this same issue with electrolosis in the heater core? Just wondering if there are very many issues with the 2004 trucks? I tried searching for the issue, but I only get the older pickups on this.

 

Electrolysis can occur on any vehicle, I would say the '04-'08 F150's are no more or less prone to it. This is usually an issue on vehicles that haven't had the cooling system properly maintained by doing regular flushes.

 

you can add another ground strap from frame to cab and engine to frame to help keep electrolysis from happening.