What are you guys doing about your cat? I have spoken with a few exhaust shops about cutting and boring out the cat to 4". Is it worth keeping? Also, where are you getting your emissions testing done? How are they reacting to your mods? Any information is greatly appreciated.
Thanks.

Im in Colorado Springs. A friend of mine has a 01 duruamx and he's running a 4" system with no CAT.Im actually planning on doing the same. Another guy on here from Denver does the same as well.

What about the LLY motor? Has anyone encountered any problems with stealership, or emissions testing after removing the cat?

i haven't had a emissions test yet on my LLY, but i still have the cat there but it is hallowed out... and as far as im concerned the cat is there mainly for a visual inspection more than anything... and i work at a dealership so it hasn't brought any problems yet.. but do make sure you put in the egr block off and the fingerstick.... that was teh only problem i had when i opened up the cat.. started setting an egr code but it was easily fixed...

:welcome2:

max08;

welcome to the DP !!!

There are a number of members here. I don't know of any with cat's. I bought mine in the state and did not come with one. Just buy an aftermarket exhaust kit (not the cat-back) and forget about it. CO does not inspect trucks/cars . . . they just do emissions testing.

Deadeye, are you sure about the inspections? I contacted the clean air bureau and they stated they are doing inspections now.

news to me. I would contact a place that does diesel emissions and see what they know. I would expect that if the state was changing the process there would have been an article in the newspaper and I have not seen one. per my experience, the diesels are put on a dyno and the exhaust is tested. If you are concerned about your emissions you could run some B20 in you tank for the week before you go to emissions. Also, you could PM SD, 4x4man, duramaxedout, GMCSLEHD, or IBDMAX'IN and see if they have read anything about a change in the emissions/inspection. I don't think any of them have a cat.