I have a 2003 5.4 eddie bauer expedition. I bought it used, wholesale, for 8,000. The very next week the check engine light came on. Took it to ford who said the code that was showing was the catalytic converter assembly. They said 1700 for the part, 300 for labor. My question to everyone is, I see advance auto and places like that have replacement assemblies for 300 to 400, for direct fit, universal cats for 90. If I buy a 300 dollars direct fit replacement, will that work just as good as the 1700 dollars Ford one? Will it turn my check engine light off? The vehicle runs perfect, no signs of any problems right now, so i am lucky in that aspect. Hope someone can help me out. Thanks.

 

The CATs on our 2003 5.4l were clogged and the engine had no power above 3000 rpm.
Replaced them with a set from Eastern Catalytic and it runs great with no codes.
I did the install myself and figure I can replace them 3 more times for what Ford wants for them.
What codes were you getting? I only had misfire and running lean codes.

 

I went to the dealer about a month ago, I want to say the code was 4020, catalytic converter assembly. Mechanic told me that the bad cat was brown on the bottom. I dont have any misfires, doesnt seem to run lean, no bad exhaust smells or burning smells. Runs like brand new. How much was that Eastern Cat? I was told that its simply 4 bolts, no welding if you get a direct fit, is this true? My mechanic skills are limited to changing out a brake light assembly so not that mechaniclly inclinded.

 

You might have had a code P0420 - catalyst efficiency low - bank 1.
I have this code reader - CAN OBDII Code Reader with Multilingual Menu
I've seen it on sale for $39.99.
It comes with a book with the codes in it.
The codes are in a format like this - P0xxx.
I keep the book and reader in a plastic pencil box that is commonly used in school.
The code reader can clear the code and then it might come back.
How many miles on the car? Ours had 120k when the clogging started.
Is the brown cat on the right side?
You can get just the right side at - Eastern Catalytic 30466 at AutoAnything
Eastern has a better warranty than some others.
I'm not sure how well a new right pipe will fit into the stock Ford left piece.
The slip fitting is slightly different looking.
I changed both sides and it took around 3 hours.
There are 4 nuts at the exhaust manifolds, a U-clamp connecting the Y-pipes and a flange plate just before the muffler.
The trans mount beam has to come out (6 more bolts and support the trans).
I removed the 4 oxygen sensors before pulling the pipes out.
One of the upper sensors was impossible to get to the connector so I cut the 4 wires and made an extension cable.
Now it should be a lot easier to replace that sensor if I need to.
Put everything back together, it runs great and no codes.

 

If you're correct and the code is a P0420, then the problem could simply be the downstream O2 sensor on the passenger side. It could also be a damaged wire running to that O2 sensor.

 

I would certainly get another opinion from an independent shop that has a good reputation in your area. A "Bad" cat usually shows more symptoms and from your description I think alloro's opinion is closer to the correct one.

 

Thanks everyone, i saw that o2 senors are pretty cheap, would a specialized tool be a good investment to change the senors out? And yes the brown cat was on the right side. From what i have seen the right cat from ford is 1700, i think the left was around 1300. I have a good friend that is a certified mechanic, he is a shade tree mechanic though, but he is a former NASCAR pit crew member so I trust his opinion, may have him look at it and tell him what you all have told me and go from there.

 

Since I had to remove all 4 o2 sensors to change the cats I picked up a spare in case one broke. I used an open end wrench with no problem.