AUDI catalytic converters

Do I really need to go with OEM cats @ $1,000 each on my 99 A6 quattro (165k miles)? I hope to keep it alive many more years, this is the first replacement of the cat, my mechanic, very trustworthy, says the other could go at some point as well. Does the first one going bad mean the next will go soon? Do I want aftermarket at 40% of the cost, or should I just bite the bullet?

What is causing the cat failure?

I think I’d go OEM on this car. What does your trustworthy mechanic recommend?

yeah, good ?? - he just says he cannot guarantee the life of the aftermarket - so I guess I should trust him some more. I just was also not clear on whether the second cat would fail soon, now that the first has - is there a relationship there? Other than the expected life of the cats, which I assume are from the same original mfg’er. Thanks

There are an equal number of people who will say you can go aftermarket.
Why change the catalytic converters (“cats”), at all? Has the cause of their failure, IF they have failed, been found and fixed? If so, what were those causes and repairs? What are the codes?

I’d go with the aftermarket cat. All catalytic converters be they OEM or aftermarket must meet the requirements set forth by the EPA for contruction and function.


That is a 10 year car, hands down an aftermarket part(s). Realize there are no real OEM parts now, just an aftermarket company making the part for Audi and Audi badges it as their own and OEM. So if you are lucky that aftermarket part may be what Audi uses anyway.

The cat. is probably good what is bad is the mechanics diagnosis.

Post back what tests your mechanic performed to determine your cat. was bad.

Many,many cars never need a their lifetime.