What causes this? a buddy of mine with a '98 5.4L F150 has burned out cats, and my bro used to have a old 302 5.0L and had the same problem, but what causes the cats to get all burned up? If there is a way to prevent this from happening to one of my trucks please tell me before it happens

 

Well, although your friend probably isnt covered, you are likely covered by the federal emissions warranty, where things like catalytic converters are covered for a longer period of time than the regular warranty. I think it is something like 8 years or 80,000 miles... of course, having an 01, you might be over the 80K anyway.

BTW, to actually answer your question Cats are burned out by getting too hot... they get too hot by getting too many deposits built up in them. This can be caused by many things, but usually by letting them idle too much, and not blowing the carbon out, and by poor fuel quality.

 

oh ok, yeah 83,500 buddys well past 100k, my bros been known to let the engine idle for 3 or 4 mins often, I do so it winter too so my heater is ready when i come out to drive. Guess i'll be extra cautious

 

Cats are just one of those things. The do go bad, but not often. In all the years I've been driving and all the miles I've driven, I've replaced 1 cat on my last truck.

 

The cat(s?) went bad on my last car, a 97 Jeep Grand Cherokee with the 4.0. I'm planning on solving the cat blow out issue by hollowing out my cats soon...