New member. Have a quick question.

[donjetman]

Hello, I just joined the group. I have a quick question I’m hoping one of you can answer. I have a 2007 Yukon Denali 6.2L. I’m wanting to do some exhaust work. I’m thinking about a Super 44 or Super 10 Flowmaster. My question is what is the pipe size that’s on my truck? I’ve heard people say 3” and others 3.5”.

Welcome
I have the same vehicle as you. I went out and measured. It's pretty much 3.5" OD from where the Y meets, all the way back. There a couple of spots where it necks down temporarily to 3.25" OD. Before the Y it's 2.5" OD. Stock exhaust has 165k miles and it sounds SWEET . Not too quiet, not too loud.

 

[DaDenaliDude]

Welcome to the Forum from NH.

Lots of knowledgeable folks here who freely share their knowledge, experiences, and perspectives. Knowledge is power.

I hope that you will become a participating member in the Forum's discussions.

Pics of the truck, please.

My understanding is the the inlet pipe into the muffler is 3.5" and the outlet pipe out of the muffler is 3".

Thank you. I will post some pictures this week. I’m waiting on some headlights that I ordered that should arrive tomorrow.

 

[DaDenaliDude]

The Walker website shows 3" ID tubing with a 3.5" exhaust tip. I'll put a tape around mine tonight when it gets back to double check.

If you travel alone and like to hear the motor more than the stereo, the Flowmasters are awesome...

I’m with you on that. I’ve had Flowmaster 40 series on all my previous trucks. But they were all 5.3. Might be too loud on this 6.2. (It’s a family truck.) Someone on FB said they did a rear resonator delete and it made it purrr just enough where it’s not obnoxious but it doesn’t sound stock either.

 

[DaDenaliDude]

Welcome
I have the same vehicle as you. I went out and measured. It's pretty much 3.5" OD from where the Y meets, all the way back. There a couple of spots where it necks down temporarily to 3.25" OD. Before the Y it's 2.5" OD. Stock exhaust has 165k miles and it sounds SWEET . Not too quiet, not too loud.

Thank you for doing that. I currently have a stock exhaust system as well. It does sound pretty good, I’m not gonna lie. That 6.2 sounds amazing but I was considering replacing the muffler with a Flowmaster to have a little more sound. Someone said that removing the rear resonator and keeping everything else stock gives you a nice little growl on a cole start and when you accelerate. But that again is nothing crazy and too obnoxious.

 

[DaDenaliDude]

x2 on this one. 3” ID w/ 3-1/2” tips.

Welcome to the forum - Michigan here, but I spent many of moons down in NC.

Whatever you decide to go with, just make sure to consider the amount of heat dissipation from your new gear. On some rigs depending on the engine size and style/size of the upgraded header/exhaust there may be a need to either wrap them with a heat tape and/or the need to wrap some of the other “components” (including but not limited to spark plug wires/boots, starter and the electrical wiring running to the starter, tranny coolant lines near the headers…etc).
When I was looking for a new exhaust (2011 Denali 6.2l) I’m pretty sure Doug Thorley shorties were one of the few headers (aside from custom work) that worked with our big @$$ engine, without interfering or needing to wrap EVERYTHING - headers, plug wires, starter and electrical.
Don’t let this sway you, rather just giving you some food for thought.
Plus I know NC has some emissions laws, so be mindful of any cat or muffler deletes.

Thanks for the response. I’m not considering doing anything to crazy seeing as this is my family truck. I just want a little more sound and to be a little shy from stock. You’re right about emissions here in NC. I plan on leaving the exhaust system for the most part stock so I can still pass the emission test each year, with that being said I’ll more than likely just go with a well known Flowmaster muffler and see how it sounds.

 

[TollKeeper]

The resonator delete works well, unless you have a AFM/DOD truck, and than when cruising, it sounds weird, when it cuts it down to a V4.

 

[avalonandl]

The flowmaster 10 is way too loud!!!

 

[swathdiver]

There are lots of videos on youtube where pickup owners deleted the muffler and kept the resonator to eliminate drone and sounds great (subjective). Glad Don got to put a tape on his exhaust, every time the Sierra came home it was raining.

 

[swathdiver]

I’m with you on that. I’ve had Flowmaster 40 series on all my previous trucks. But they were all 5.3. Might be too loud on this 6.2. (It’s a family truck.) Someone on FB said they did a rear resonator delete and it made it purrr just enough where it’s not obnoxious but it doesn’t sound stock either.

Just measured the Sierra's exhaust, 3.5" before and after the muffler.