What did you do to your NNBS GMT900 Tahoe/Yukon Today?

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iamdub

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From the crossmember after the third cat, back to the exhaust hangers in front of the axle, 40".
Since I have the three and a half inch stainless works exhaust on there, they have a little bend to go from the y-pipe and move it over a little so you can run a center inlet center outlet muffler.
From the end of that bend to the exhaust hanger is about 30"
The first thing I did to this exhaust was cut off the resonator on the stock system because it was hideous hanging underneath the back there behind the rear tire. So I really don't want to put anything on that section of exhaust again if I don't have to but we will see what I figure out... Turns out 3.5 in piping isn't as common as three or four... Not as many options as I was hoping for. Looking at some Walker quiet flow stuff, or maybe even a combination of different style flowmasters... A little disappointed in not finding what I want in the sizes I would like.
The two different mufflers I've tried after getting rid of the factory one, have both had drone to some degree and I really want to avoid that. However the factory muffler with no resonator didn't sound any different to me in the car.
I had a set of flowmaster dbx mufflers on my subaru, and I have one on my little 1.8 l Chevy LUV and on the Subaru they were barely noticeably louder than stock and had zero rasp and sounded decent. And on my little truck almost the same deal. Very quiet and zero rasp.
So I was trying to find one of those to use as a resonator if nothing else, but I would have to go up to a 4-in and when I do that it's a 20 inch long muffler so that doesn't leave much room for something else in there.

Look on FB or CL for someone selling the stock exhaust from their diesel truck after they upgraded it. That's how I get 3.5" exhaust for DIRT CHEAP.

I barely noticed the slight difference when I deleted my resonator, too.

If you find a muffler setup that you like in volume and sound but has drone at a certain RPM, you can add a Helmholtz chamber to nix that drone. I have no drone with my setup. I think chambered mufflers are more susceptible to causing it.
 

RooTBeeRthe1st

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Look on FB or CL for someone selling the stock exhaust from their diesel truck after they upgraded it. That's how I get 3.5" exhaust for DIRT CHEAP.

I barely noticed the slight difference when I deleted my resonator, too.

If you find a muffler setup that you like in volume and sound but has drone at a certain RPM, you can add a Helmholtz chamber to nix that drone. I have no drone with my setup. I think chambered mufflers are more susceptible to causing it.
I'm not too worried about the cheap part. I just want to try and make it as quiet and stock sounding as possible while still being able to flow quite a bit. Even though those don't really go hand in hand
 

iamdub

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I'm not too worried about the cheap part. I just want to try and make it as quiet and stock sounding as possible while still being able to flow quite a bit. Even though those don't really go hand in hand

Well, my focus was more on availability than cost. It could just be in my areas, but there are always kids buying diesels and the first thing they do is delete the muffler or slap on a 4" (or larger) aftermarket exhaust.

If you still have cats, then that 22" muffler will be about as quiet as stock (but have a better note) and will flow as much as you could possibly need, depending on how much boost you plan to throw on it. Worst case after boost, you step up to a straight-through muffler for a diesel.
 

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