I'm trying to figure out how many people out there had to replace their catalytic convertor on their E320 '95-'02 after 80K miles. From my research this looks like a possible class action law suit but i want hard evidence.

 

Haven't replaced it but I'm getting a nice rattle from under the car which I have heard could be coming from the cat converter cover coming loose. It's annoying.

 

You will get no where with a suit,the action was taken up years ago thus the 8yera /80000 mile which ever comes first rule.
after 8/80 you are on your own as common neglect,ignoring check engine lights,poor maintenance etc.all out of control of mb can cause cat failure.A properly operating system in a non rust belt area maintained properly can last well over 150k.
past 8/80 go to racepages.com and get the universal oe cats for 65 bucks and splice them in.
ohlord

 

Hi,

I agree that you are unlikely to get anywhere due to the arguement that so many factors are outside of MB control.

I tried hard and long with MB over this issue and in the end although MB actually agreed with my technical reasoning (there is a technical issue at the root of this problem) but I was unable to persuade them to make a contribution because UK warranty at that time was I (YES ONE) year only.
You guys in the States are cushioned from reality! 80k miles is disappointing and obviously not aligned with your expectations but this is not an unreasonable life on such a component. The real issue is why MB choose to rape its customers by charging (in the UK) in the order of 2500USD to rectify this issue. This is shear greed since even genuine MB OE supply (i.e. manufacturing) cost must be less than 100USD.

From my limited experience the V6 320 M112 engine is specifically prone to this issue and it has little to do with user "abuse" unless you define "abuse" as normal driving. i.e. Hot\Cold cycles with occasional water spray.

The problem is due to the intumescent http://en.wikipedia.org/wiki/Intumescent material used to locate the catalyst brick degrading and "disappearing" out the tail pipe. The brick can then rattle and over time begins to break up which in turn allows it to rattle more.

Initially the rattle is only when cold but gets worse and worse with the final problem having the potential for "blocking" the exhaust outlet as the brick orientates across the flow or actually lodges in the box outlet.

Usually its the gearbox located cats that highlight this problem due to the horizontal installation and trilobal shape which exacerbates the problem. In addition this location is more exposed to cross spray from the wheels.

Assuming that the catalyst has the DESIGN/test capability of completing a life in excess of 80k/8 years my personal view is that MB had (maybe still have) a manufacturing compliance issue on the trilobe stainless casing.
The welded seem of the "clam shell" design does not align perfectly (I have pictures of this feature if you provide me with your real email I can send them if you wish) causing the CRITICAL preload conditions on the intumescent material to be out of spec. Basically a good overall design let down by badly executed / controlled manufactiring conditions which as many of us know was due to poor Quality control procedures at Worldwide suppliers when MB increased its use of Worldwide sourced parts (for cost reasons) as did many other manufacturers) particularly during 2000/2005.

I resolved my issue by removing the bricks on the intermediate cats entirely (kept the original casings) since this made very little difference to the emission output which continue to far exceed the requirements of UK annual emissions test.

However the used vehicle emission requirements in the States maybe/are somewhat different and I suggest you follow ohlords advice.

Stuart

 

How can I remove the bricks myself? Do I have to get into welding? If it's simple enough I'd like to have a go at it.

OhLord - I found the $65 cats at the site you recommended. So, if I do go this route, all I have to do is order them and tell my shop to cut out the old ones and weld in/splice these new units? That's it?

Thanks in advance.

 

yep you have to cut the case at the existing weld to remove the brick.

To fit the low cost after market cats you will need to weld the system up anyway taking grewat care that clearances are maintained. The MB cats are triangular in shape. The aftermarket ones are likely round so cleearances will at best be different. The MB inlet and exits are also somewhat skewed so careful jigging is required.

Good luck.

Stuart

 

so I called racepages customer service and they said that the universal cat conv listed there will not work for the 4-matic E320. It will only work on the standard RWD version...

Stuart or anyone else - do you know if this is true? Why is that?

 

Most likely there is inadequate packaging space (i.e. room) available. This is why the MB cat is triangular in shape.
The 4matic has a diff in the gearbox that takes up extra room.

Maybe it isn't space but the fact that the cat is required to work harder on the 4 matic and the non OE part only has "standard" performance. performance is gained by increasing size.

My best guess.

Why not ask the supplier who gave you the info in the first place.

Stuart.

 

Google eastern catalytic and ask for an application that fits the 4 matic.We have had members that got them and a good muffler shop fit them in.Some shops also have retro fit universal cats they can find an application that will fit your car.
ohlord

 

Federal service life in US is $80k
It is also a felony in the US to tamper/disable the cats.