BMW X5 Catalytic Converter
 

I have been having this problem with my V8 2001 x5. from SES lights going on to oxygen sensors being replaced. Now I finally have taken it to the dealer and their telling me now that I have to replace the left cat. at an estimated $2000 cost. I went to a muffler shop who quoted me way far less for a universal cat. my question is has anyone replaced their oem cat with a universal cat and have they had any problem? let me know please I want to fix the problem so I can enjoy my truck without all of the noise coming from the cat.

slightly off topic, have you been running the x with old spark plugs? because a mechanic told one time running the car with bad plugs could cause cat problems. can anyone confirm?

BMW X5 catalytic converter
 

well the spark plugs have been replaced, so I', not really sure if that was the reason why. Have you replaced the cat?

I don't know if this helps, but on my 97 M3, I was told I needed a new CAT in the near future. Half of the people said universal would be fine, and the other half either said some places won't even bother installing them or they fail in 2 to 3 years. I don't know if this applies to newer BMW's, but they have tricky exhaust systems.
I know one way to tell if you have bad CATs is to either jack the car up or get under there and hit the CAT with a rubber mallet and see if you hear any rattle or noise.

I've personally not used a "universal", (nor had to replace a cat),
but friends have: on everything from Vettes to beaters to M3s...
they all went with a "universal" from someone. They all came with
a 'cert' and a guarantee to pass emissions.

Unless you have a bro-n-law in the BMW parts dept., I do a search
on the web and check out non-oem prices or, your local joint that
you contacted. I wouldn't give it a 2nd thought, other than being
sure it is the cat.
GL,mD

BMW X5 catalytic converter
 

yeah I get the same reaction from people I ask. I just dont want to give $2000 to the dealership to replace one Cat not both but one. I have taken the car in to the dealership and they tell me that I need a new cat. everytime I revv the engine I hear rettling noises coming from underneath the car. so I know one cat is bad. but my ultimate question is will a universal work and will there be any problems after I change them out.

[quote=joeblackx5]yeah I get the same reaction from people I ask. I just dont want to give $2000 to the dealership to replace one Cat not both... ...but my ultimate question is will a universal work and will there be any problems after I change them out.[/quote]

I can't promise you a thing...but, if it were my car, I'd get a non-oem
cat in a heartbeat.

By the bye, Joe...
our '01 cats are "covered" for 8 yrs or 80,000 miles,
whichever comes first.

For future reference,
do you have to have a check engine light or something wrong like that to get your cats replaced for free under the 8 / 80,000 warranty. Or can you just take it in and tell them you hear rattling?

Sorry to thread jack, but it is part of the topic

No clue...but, as I was responding to Joe's wonderment over oem
cats vs. aftermkt, it was nagging me that it might be covered;
so, I ran down to my X and looked it up. It may be moot as I don't
know his mileage. But, it's ammo...I suspect there is a fairly easy
sniffer test to determine if the cat is shot or it's something else.

For fut ref, there is that seperate booklet that came with the Manual
and audio book; it's the "maintenance book" and in the back section
it details the stuff covered under Fed law, time and distance.
GL,mD

I had the 80K miles discussion with the dealer and was basically told "you'll need a order from the Feds before we'll pay for replacement under that warranty". Not for a "cat' but emmissions related repair.

yeah at the end of the day we are still in the mercy of the dealer. I am going to go with the aftermarket and I will keep everyone posted. Hopefully the next person who has the same problem can learn from my mistakes. Thank you all and of course if there is any other info re: cats out there I should know please feel free.

One quick question to anyone that might know. I am looking at different aftermarket cats, where can I find out info on my x5's current cat (inlet size and outlet size and length) I have an 01' 4.4i where would this info be located? I tried realoem but no luck.

Try an after-market exhaust maker and see how they spec. the exhaust.
I found this link:

http://www.millteksport.com/products.cfm

It contained this info:

Your original catalytic converter will typically have 400 or 600 cells per square inch (cpsi), these original cats are restrictive in their flow, typically allowing an open area of around 55-65%.

Joe, Zulu's link is good and,
here's a look from GOOG:

http://www.google.com/search?hl=en&q...=Google+Search

I bet there are a few shops in NYC/NJ that have them to fit yours.
Like putting on aftemkt mufflers, those guys are generally pretty
good at making things "fit". $2Gs from the stlr?! I would go aftermkt.
It's a cat...
GL,mD

Thanks guys. I dont know what I would do without X5world.

Me neither!

+3 !

Quick question, I might have asked this before but I am not sure. I am buying a universal random technology cat and they have several for the x5 size wise they range from 2" inlet and 2" outlet size all the way up to 4" inlet outlet, also the length varies from 17 inches all the way to 24 inches. My question is does anyone know what size a 2001 bmw x5 4.4i take or where can I find this info? thanks again guys.

Here's a parts diagram, but it doesn't show dimensions.

I have to think that a cat mfg'er has the right size if
you offer your MY, month built, engine, etc.

And, a scooch under your car with a tape measure
should give you length at least...
GL,mD

http://www.realoem.com/bmw/showparts...90&hg=18&fg=10

Quick bump for query on how the aftermarket cat held up? I just got back from the stlr and it wasn't as bad as I thought. $823 for bank 1 cat. Still a little more than I'd like to pay though, lol.

Anyone have a (good) used one lying around by chance? Lol.

X5 takes a 2.25" cat. Mine recently blew out, and were replaced with Random Technology high-flow units. They work great, added more power, and do not throw a CEL. You also can see right through them.