Have a 99 & 2000 E320. Both have mysteriously come up with cracked cat converters. Any word on this being a larger issue than in my house? Seems like an odd problem, much less having it happen on 2 diff vehicles.

 

You say cracked. How do you know?
I assume you mean they rattle when cold. Yes?
If so this is a very common problem.
I have experienced two identical failures on a R170 SLK and w220 S Class.
Many other instances have come up on this site and at our local dealer.
The rattle actually comes from the packing material that holds the monolith (brick) in place being blown away (design/manufacturing issue) which in turn allows the brick to move which in turn allows to brick to begin to fragment at the points of contact. Eventually the brick gets worn down to a tennis ball size and then you can end up with a block system etc.

Cats are susceptible to damage from grounding, water, engine malfunction etc and my experience is that MB wil not entertain any sort of redress outside of warranty since in their words they cannot control the operating conditions. I accept the grounding issue but this is obvious by visual inspection. But water!!...is it my fault that it rains here in the UK!
It is my belief that failure within warranty is high but I do not have the figures.

Have a look at the cat caseing (probably made by Zena Starker) for a code which aligns with the manufacture date. Both of mine were not the original cats. They had been changed in warranty again supporting the premise of early failure.

This issue has done a lot to sour my respect for MB. It is my belief that they are aware of a problem but will not do anything to address the situation.....and I've tried!

Unfortunately cats are very expensive.

Its all about LIFE EXPECTANCY vs COST of replacement parts.

If you would like pics of codes, failed components etc. send me a PM with your real email. The site won't allow me to attach (resized <200k) pics.