Hi -
4.6L DOHC
My driver's side catalytic converter is making quite a bit of noise during acceleration when the engine is warm.
I have no trouble codes, no cel and the truck seems to be running fine in general.

I am exploring repair possibilities. I've talked to two shops - one general repair, one exhaust specialist. Neither gave me any options other than to replace the whole system for around $1k.
That isn't an option. I'm a semi-competent home mechanic and if that's what has to be done I'll just buy the walker system from RA and do it myself.

OTOH - walker lists a universal replacement P/N 93252 that I can get for <$75.
Should I just keep calling exhaust shops until I find someone that will cut out the old and weld in the replacement? Or is there a valid reason this isn't a good option?

 

Is there a chance something is rattling around between the heat shield and the catalytic converter? Can you even get a good view to check it out?

 

Your truck uses three cats. If it's just the rear one that is bad, then it can be replaced by itself but the two upstream ones need to be replaced in a pair or the computer will freak out.
You can get them all individually for about $120 each from O'Reillys, but once the pipe has been cut apart and welded the price won't be too far off from the full y-pipe. You can get the y-pipe with all three cats for just under $1000 and change it out yourself, it's a bolt in job.

 

It's the drivers side forward cat.
There is no heat shield.
I was under it on the lift at one of the shops. It's also easily accessible on ramps. At worst it looks like the front driveshaft might have to come out to get a saw/welder in position.

I'd get it a little higher than just ramps if I decide to do the whole system myself.
The walker stainless system with all 3 cats is currently $415 shipped from RA after mfg mail in rebate.

 

Is the system bolt on ? the one you reference ? If so .. I would go that route . Buy some GOOD jack stands and change the system yourself ! Best of luck !

 

BS, you can replace them individually no problem. The computer won't freak out. It will freak out if substandard quality parts are used though, or if there is an issue that caused the original to fail and that issue isn't also corrected. The '03 and newer are known to have this issue however, its an inherent design flaw with the type of fabrication method Ford elected to use (the system is actually made by a third party company, so its a third party design flaw.) Universals if you use the right type do fix the factory flaw. There is a pretty good chance the other side might not be far behind, again, it is a design defect that causes these to rattle loose and break over time. the third cat in the system usually doesn't rattle loose or break, but it can get plugged with debris from the front ones if they come apart. The third cat can be replaced with a cheaper low cost unit, since it is not monitored by the OBD-II system.

I double checked and that Walker part might work, but just because it says 1996 and newer and that it works with OBD-II is not good enough. Chances are your vehicle meets either LEV, NLEV, or ULEV standards, and/or CARB requirements. Its not the year vehicle that decides which cat is appropriate, its the emissions requirements the on-board computer is calibrated for. So just double check your emissions sticker. Odds are you will need a cat more like this one. Item Details

A direct fit might be a good option if you have two or more cats with an issue, but the universals are probably not going to be as expensive as suggested by others. Sure the cats can cost a decent amount, but welding is not usually that expensive, depending on the shop you use of course. Also in a bolt on, you do get what you pay for. Walker is a good brand, and they do use the right loadings in their bolt on product (when you buy a universal you may not get the right loading the vehicle needs) Eastern is a good brand too.

 

I replaced the entire exhaust - 3 cats on the y. PITA to get some of the nuts off the exhaust manifold bolts and had to drop cross member that supports trans. No way to cut forward cats out without removing. No room to maneuver. I paid $599 for mine at Autozone for 03 Explorer 4.0 L V6 SOHC.

 

I have had a single side cat replacement throw a cat efficiency code for the other side after the second or third drive cycle. I spent some time in an exhaust shop in the early 2000s, tons of fun having a customer come back and scream at you about not fixing it right or making something else break on their car-

 

Well, I sucked it up and bought the system.
A paypal discount showed up via email, plus walker's current MIR, I ended up getting it for just over $400, and I might have gotten $100 in rewards through Autozone as well - not sure though, still waiting to see that in my acct.

I don't have immediate plans to do the replacement, but I expect it will be done sometime in the next couple months.
Truck is still running fine.
I'm not sure which noise bugs me worse - the exhaust or the rear end.

 

BEFORE YOU EVEN START ... SPRAY ALL NUTS AND BOLTS WITH PB BLASTER! lol and let it sit for a while. You might even want to spray it the night before you work on it and again in the morning. Will probably save you some busted knuckles and swearing

 

The guts in these cats break loose and start rattling seen it a number of times. I have used the Walkers before they work ok. But not always a perfect fit.