So I have a 03 Expy with the Triton 5.4, bad loss of power lately. Replaced the plugs and packs, fuel filter, no luck, mechanic says bad cats. being an 03 and not worth putting too much money in it what are my options? Has anyone actually had experience gutting or straight piping the cats? Will it effect the computer and how it runs? We don't have inspections down here so thats not an issue. Thanks all

 

This is an old thread. But you can remove the cats on both sides, weld in pipes, and then use spark plug anti fowler's on the rear O2 sensors, drill out 2 of them, and stack the drilled ones with the non drilled ones, install your O2 sensors, and screw back into the O2 holes. They CEL light will stay off. I've done it on my 2003 Expedition without any issues.

 

I figure I will leave the O2 sensors as is .....they are new ..... then cap over the hole I cut in the cat's