I have to replace the catalytic converter in my Bravada. When looking for a replacement, I came across this on Autozone'* website:
I haven't had a chance to check the owners manual yet and I'm waiting to talk with my dealership, but I would like to know (hopefully before I talk with them) so I don't get a song and dance routine. They already told me that the hesitation that I was having was a 'characteristic' of AWD vehicles (half throttle from a stop feels like it'* only idling along, but give it full throttle and it goes... decent, but not like it should). And now I have a rattle whenever the car is on a slope, nose down.

Please let me know ASAP!
TIA!

Ok well, here'* the update since I didn't get any response.

Talked with the dealership and they are going to check it out and see if the cat is bad. It is covered (any 95+ car) for 8yr/80,000mi. From what I gathered from the dealership, this is a federally mandated emissions control device warranty.

Now the only problem is going to be getting them to change it. Here'* the symptoms. Until the cat heats up (~2-3 minutes), my Bravada has ab-so-freakin-lutely no power unless I kick it down and the engine screams. Once I make it to the end of my road (between 1/8mi & 1/4mi from my garage to the stop sign), it is much better, but a bog is still there, just less evident. Getting the dealership to notice this is probably going to be a problem. I have to tell the techs to just jump in and drive it right away to notice the problem.

I just replaced my cat (sigh), and my symptoms were that it was just fine idling and in the lower ranges, but try to rev it up beyond 3,000rpm and well...it wouldn't. No power whatsoever, and took forever to get up to speed on the highway (so that'* what it'* like to drive a Kia! *snicker*).

My guess is that if your cat is bad, you should be able to move at low rpm, but at high rpm, it won't be able to flow enough and you'll get no power up top.

Well, put it this way, I believe it'* on its way out. Before the cat warms up, the truck will barely get out of its own way. The rattling got a bit worse today and it now rattles when I drive out my driveway. Who knows, but it needs to be fixed.

You should also have them inspect why the cat failed so prematurely. In theory, the cat should outlast the car. With less than 80,000 miles on the truck, there'* likely something that contributed to its premature death.

Consider some of these reasons for the cat dying prematurely:

http://www.discountconverter.com/Why...erproblems.htm

Upon further thought, I believe that the cat element is just starting to work itself loose and that the underlying hesitation problem is trans related. I am thinking about purchasing a extended drivetrain warranty through the dealership so I don't have to worry about it. The warranty costs less than the transmission (for a 3yr/up to 100,000mi).

I had the trans fluid and filter replaced today, because records didn't show it ever being done, and the hesitation is much less noticeable. The filter was loaded with crap, the fluid smelt burnt, but the magnet was quite clean. I don't know what to make of this. It is quite possible that the filter restriction was the problem and that it'll be fine.

I am by no means an expert on either exhaust or transmissions. I have never had these symptoms that I am experiencing now so I have to ask others, that have more knowledge than I do, for suggestions based on the symptoms.