I have read many a thread on the removal of the CAT. I would like to do so to reduce EGT's and backpressure. I understand there are no sensors past the CAT, but I have heard that some people are having issues with fuel smell in the cab afterwards. I was wondering if some of you could chime in and share your experiences. I tow a 12k 5th wheel and have the family (including a 3 month old) to think about with fumes etc. I do not have to worry about emissions testing however.

I was one of the very few that had issues, but I replaced the entire exhaust, not just the cat and ended up putting the stock pipes back on. From what I hear, most that remove the cat on the LLY or replace entire exhaust are also doing the EGR blockoff plate and the finger sticks.. seems they are all having good results.

personally I am about to order an LB7 front pipe for my LLY and keep the stock muffler in tact. I basically want the same as you, lower EGT's and possibly better mpg and I have heard as long as you have some type of backpressure then the EGR should be ok..I will find out.

the guy I sold that entire exhaust system too says he is getting 80 more miles per tank. GRRRRRRRR

Where are you going to order your downpipe? Since you are planning on it, I assume the LB7 is the same just w/o the cat?

I will be ordering from Mark and DPP(one of the vendors here) www.dieselperformanceparts.com (http://www.dieselperformanceparts.com/)

Its an MBRP part and the number for the down pipe with no cat and 4 bolt flange is.. #GMS9401 I think he said it was $122..I have the email at work.

probably find it at the dealer as well, but I would rather support the vendors here. :ro)

Sounds good - I am familiar with Mark - I bought my gages from him. Whats up with the 4 bolt flange? Is there anything else you need to install it?

nothing else to install, it bolts up to the stock pipes as well as MBRP pipes.

Sounds Great - Thanks for the info.

hold off on this unless you have talked to Mark arleady..I am on the phone with DPPI right now and they are telling me this pipe will NOT work with the stock flange.

CORRECTION.. the GMS9401 WILL fit the stock flange..he just called back after talking to Mark.

Great - Thanks again.