GMPP Touring Muffler

TimmyG · June 15, 2012

Being on clearance i had to jump on this!

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jimbrown1 · June 15, 2012

I apologize for the delay, as it has been an extremely busy week for me. The video quality is not that great as it was shot with my iphone. The audio does not really capture how low the tone is that well.

Cold start and idle

http://s25.photobuck...nt=5ba542db.mp4

Light acceleration- Windows Up

http://s25.photobuck...nt=b128da67.mp4

This video is of the same muffler as well and captures the sound/tone better than my videos.

Sounds great. Did they use the stock hangers for the Borla muffler or did they have to create hangers? The site sys it's for 2.75" diameter systems, so i assume ours are 2.75" and not 2.5".

scottmoyer · June 15, 2012

I called Borla again to ask about installing this. The end of the muffler pipes are notched. I asked what those were for and Chris said that these are the clamp on style mufflers. He recommended AccuSeal clamps instead of the standard saddle clamps. I need to get a couple and I'm ready to go.

I checked the hanger positions and found that the forward hanger is only 1.5" from the factory muffler welds and the rear hanger is at 4" from the welds. The factory muffler is 25" long where the Borla is 24". The Borla muffler pipes are 2.5" on either side of the muffler for a total length of 29". By my calculations, if I can cut the forward muffler pipe right at the welds, and slide the entire 1.5" of pipe inside the Borla muffler pipe for clamping, the rear edge of the muffler will be at the same position as the stock muffler. As I mentioned, there is 4" of pipe at the rear before the hanger. If I cut about 1" from the factory muffler weld on the rear side, that will allow the rear piping to slide inside the Borla 1.5" and all factory pipe placement will remain exactly in the same position utilizing the same hangers.

Simply put, cut the pipe as close to the muffler can as possible on the forward side and 1" from the muffler can on the rear. If 1.5" of pipe will slide inside the Borla pipes, the Borla will be hanging in the exact spot the factory muffler was.

scottmoyer · June 16, 2012

Last update. I went looking for the band clamps that Borla recommended for the install and didn't find any. A local muffler shop said he weld it on for $35. I said, "Ok, let's do it". Once the truck was up on the lift, I saw the most important part that I kept forgetting. The inlet and outlet are offset! So, it cost me a few more dollars for the shop to bend pipe and make the muffler fit. I guess this isn't a DIY in the driveway job unless you have the pre bent pipe sized and ready to be clamped up.

MB2008LTZ · June 16, 2012

I currently have the GMPP Touring cat back and just ordered the "sport" muffler from Borla....$88.57 shippped....Now I can switch it up if i want it aggressive or subtle....Glad I found this thread, I would have never know about the clearance sale at Borla with out it. Thanks guys!

BlackZ71Silverado · June 16, 2012

Last update. I went looking for the band clamps that Borla recommended for the install and didn't find any. A local muffler shop said he weld it on for $35. I said, "Ok, let's do it". Once the truck was up on the lift, I saw the most important part that I kept forgetting. The inlet and outlet are offset! So, it cost me a few more dollars for the shop to bend pipe and make the muffler fit. I guess this isn't a DIY in the driveway job unless you have the pre bent pipe sized and ready to be clamped up.

Installed my brothers yesterday. Took about 30min. Was not offset at all, everything lined up fine.

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txdox21 · June 17, 2012

Where does it say/show they are on clearance?

BlackZ71Silverado · June 17, 2012

Says nothing about clearance. They just don't cost much that's all.

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scottmoyer · June 17, 2012

The GMT800 exhaust is offset. Maybe you GMT900 owners can do the swap easier, but us 800 owners will require some additional piping.

TimmyG · June 17, 2012

Where does it say/show they are on clearance?

i googled the part number and it was listed on the clearance page

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txdox21 · June 20, 2012

Update:

I did not tell my wife about the muffler swap to see if she would be able to notice the difference inside the cab. We went on a 350 mile trip this past weekend, and she did not notice. I can definitely tell the difference in volume/tone, and would not want the muffler any louder. The purpose of telling this was to emphasize that there is no drone with this muffler.

Secondly, and most intriguing, I ran the numbers on the MPG for the trip and got better gas mileage than I have seen in the last 1.5 years. The trip was up and down through winding hilly roads and not interstate. I have never been impressed with the gas mileage of my truck and was hoping I would not see a decrease in MPG, so I am thrilled with the results so far. I have hand calculated my MPG since day one and keep a running spreadsheet. I will update this thread after a few more tanks of gas as to whether or not the increase continues.

TimmyG · June 20, 2012

My sport muffler just came!

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Mikeb52r · June 20, 2012

Ok guys, I just jumped on the band wagon and ordered mine. Can't wait to get it on and hear it!

music · June 21, 2012

I did not tell my wife about the muffler swap to see if she would be able to notice the difference inside the cab. We went on a 350 mile trip this past weekend, and she did not notice. I can definitely tell the difference in volume/tone, and would not want the muffler any louder. The purpose of telling this was to emphasize that there is no drone with this muffler.

So which do you like better... stock or the touring? I've always thought the stock exhaust on my truck sounds very good, but I also noticed that test drives in a '10 and a '11 model were quieter.

txdox21 · June 21, 2012

I am liking the touring more so far. It is noticably louder and deeper than stock, but not wake up the neighbors loud. It is exactly what I was looking for and as stated before I am glad it is not any louder.

I kept the stock muffler, but I have no intentions of reinstalling unless MPGs start to suffer or the muffler gets a lot louder over time.