I too thought some kind of secondary converter. The main converters are pretty much directly underneath the engine and look to have two O2 sensors, one on the inbound side and one on the outbound side. As far as I can tell no wiring and/or sensors on the two pods in question. Last night after she had sit for several hours, the muffler was cold, the primary converters were still very warm and the two pods were somewhere in between as far as temps go. The dealer parts diagram show the two main converters separate of course, then the assembly with the muffler and two pods. Not sure exactly...I have also been underneath my 19 and have been pondering some exhaust work. Curious what you are thinking ?
What I'm calling resonators are at the tail end of my Traverse, just before the exhaust tips. The GM parts description calls them mufflers, but then they also call the mid pipe assembly a muffler as well. So anything's possible I guess. It possibly has four converters, three mufflers, etc, etc....Don't know if there is any similarity in the exhaust systems, but the 3.6 in my Camaro has (on each side--dual exhaust from factory) O2 sensor, Catalytic converter, 2nd O2 sensor, resonator, and then muffler at the rear. Is there any possibility this is a resonator?
Not sure if you meant what was I thinking the pods were or what kind of exhaust work I was contemplating. How about you, what kind of exhaust work you thinking about ?I have also been underneath my 19 and have been pondering some exhaust work. Curious what you are thinking ?
was pondering 2 different changes:
1) Replacing that two into one muffler with straight pipe, or
2) Eliminating the 2 resonators near the rear bumper. There are several "you tubers" who have done just that and have managed to retain the OEM exhaust tips
Turned out good. An all day job Saturday, had to take it slow because I didn't have any extra exhaust parts so a lot of measuring and fitting before any cutting and welding. I did get a ten second sound byte of the original exhaust note, but haven't driven it other than off the lift, so the "after" sound byte will be another day or two. I'll post them both together soon. Here's a few pics, more when I post the sound clips. Oh, I extended the exhaust tips out just a little farther than stock, to me they were tucked up underneath the rear bumper a little too much..Curious how stage 1 of your exhaust project turned out?
Thanks. Here's a shot of the pieces I used. I know the 45 degree SS elbows came from ebay, have to look but probably the couplers/reducers did too. This is before I trimmed some of the pieces to size.Hey looks great - nice workmanship.
How did you get the bends in the stainless tubes that replaced the resonators?
I'll catch an "after" soundbyte this weekend which I'll post. I've driven it approximately 100 miles since I completed this job and two things are very apparent - one good, one bad. First the bad - exhaust drone inside at highway cruising speed is unacceptable. I've ordered more tubing to fabricate a helmholtz type resonator for dealing with this issue. The good - my mpg has definitely risen although I can't say how much. I'll have hard numbers next time I top off the fuel tank.Curious to hear how that sounds
hanks for this update - will be interested to hear the differences both audible and MPG.
Sorry to hear the exhaust drone has become an issue. One would think the ANC built into the vehicle would help to minimize this issue..