I have an 02 GMC LB7. A friend of mine keeps telling me that I need to have the muffler cut out since I don't have the money right now to go to a 4" turbo back system. He says that at lower rpms it sounds the same and sounds really good on the throttle. I imagine it will be much more free flowing too. Have any of you guys done this? How does it sound? Does anyone have any sound/video clips to share?. I was told it would only cost $30-50.

This has been discussed quite alot. just do a search of the LB7 and performance and exhaust sections, I'm sure you'll find all you need.

Do it!:ro) Its not to loud with normal driving but when you get on it people can hear you coming

Got my 05 that way. Just can't justify spending 500 on an exhaust system when 50 bucks at a muffler shop will get you almost the same thing. I had them add a 5" tip too just for looks. The sound is a litle louder at idle and at lower RPMs. Get on it, and you know it's there! I plan on getting rid of my cat too so that I can hear that variable geometry turbo whistle sweet nothings into my ear through the exhaust, can you say jet turbine?

my LLY is done that way too, sounds nice. i'm minus cat and muffler

if i remember correctly people where commenting on strange smelling exhaust once the kitty ran away? Is that true?

if i remember correctly people where commenting on strange smelling exhaust once the kitty ran away? Is that true?yes my truck smelled like a old dump truck with the cat off

even inside your truck? I'm use to the smell of diesel exhaust, I work with them all day long at CAT, but dont necessarily want it in the cab of my truck. I still have the cat on mine, and I'm thinking of removing it, but what all does it require? LB7 front pipe.... and what else.

if i remember correctly people where commenting on strange smelling exhaust once the kitty ran away? Is that true?

mine doesn't stink, stuck my nose down in it just a minute ago... smells like diesel.

even inside your truck? I'm use to the smell of diesel exhaust, I work with them all day long at CAT, but dont necessarily want it in the cab of my truck. I still have the cat on mine, and I'm thinking of removing it, but what all does it require? LB7 front pipe.... and what else.

you can just replace the front pipe with the LB7 one or replace the whole system with the 4". either wat you will need a good floor jack or a underground bay to wiggle the pipe/cat out if you dont want to cut it. you also have to undo a bracket that bolts to the tranny to make the process got faster.

hmm sounds enticing, now I've just got to find a front down pipe from an LB7

Or maybe a cat-delete pipe from MBRP?:)

I heard you can get a cat delete pipe for around 140bucks

fool32696 you shouldn't have to even have to think about cutting that muffler off. Let that duramonster breathe!!! We have five duramaxes-1 '02 with just the muffler cut off and a 5 inch turn down on it, 2 '03's one with stacks and the other with duals, 2 '05's with the mufflers cut off. Let me tell ya that the 2002 with the muffler off and a 5 inch pavement pounder sounds the best. If your wanting to wake the dead thats the way to go. Good luck!!

I went to a few muffler shops today and nobody could really help me. They both told me that they can't bend anything larger than 3" pipe and I said that I don't want a section of 3" in my exhaust. Should I look for a truck exhaust shop? Is 3.5" an odd size, neither of the guys I talked to had any?

fool, I don't know if any of the vendors here have it, but you can get one on ebay.

Is 3.5" an odd size, neither of the guys I talked to had any?

My local muffler shop ordered a section when they installed my Flowmaster muffler, so they can get it. They can not and did not have to bend it.

As for sound,
I have duels with one side being without muffler. There is a little more drone around the 2,000 RPM area that takes a little time to get use to.

I think the lly motors smell worse with the cat in than with it taken off. You cant beat the old diesel smell. After all you got to have something to remind you what your driving.

Just cut it off the muffler shop doesnt have to bend it just cut the pipe at the proper angles(use a little bit of Trig. to figure the right angle)

That's what I was thinking. These exhaust shop guys must not be too bright. When I find one with half a brain I'll get the job done.