'08 Sierra 5.3l Custom Exhaust Troubleshooting

WestTX.08.Sierra · June 22, 2008

First of all- this is my first post here in GM country so 'hello' to everyone.

My question is has anyone had any problems with custom exhaust applications while the vehicle is in the V4 mode? I spoke with a gentleman that swapped the factory exhaust for Flowmaster 40's. He said that the tuck sounded awesome while in the V8 mode, however, it was extremely loud and unbearable while cruising down the highway in the V4 mode. How's anyone else experienced this and what applications have ya'll used?

I promise I searched the forum before asking!

Thanks in advance!

iminaquagmire · June 22, 2008

Both of the mufflers I've had have been quieter in 4 cylinder mode. I've had a magnaflow 14218 and now a Dynomax Bullet. The dynomax bullet is a loud muffler too, but not so much in 4 cylinder mode. I've heard of having drone issues but I haven't noticed any.

03blackz71 · June 22, 2008

I would highly recommend the GMPP touring exhaust system. Just put it on friday and it is awesome. It has some bark when accelerating and at WOT but when cruising it sounds like the stock system. My wife couldn't tell when it kicked into V4 mode until I told her when it did it.

I too was worried about the V4 noise when I was looking at exhaust systems and I even waited a year before I bought one. So I went with the GM one just because I get deal on it and if GM sells it as an upgrade exhaust it has to be a good system with out any of the problems as a custom exhaust system.

alaska511 · June 22, 2008

I would highly recommend the GMPP touring exhaust system. Just put it on friday and it is awesome. It has some bark when accelerating and at WOT but when cruising it sounds like the stock system. My wife couldn't tell when it kicked into V4 mode until I told her when it did it.

I too was worried about the V4 noise when I was looking at exhaust systems and I even waited a year before I bought one. So I went with the GM one just because I get deal on it and if GM sells it as an upgrade exhaust it has to be a good system with out any of the problems as a custom exhaust system.

+1

I think we are the only 2 on the site that have it. That is a shame, as it is such a great sounding system.

03blackz71 · June 22, 2008

I would highly recommend the GMPP touring exhaust system. Just put it on friday and it is awesome. It has some bark when accelerating and at WOT but when cruising it sounds like the stock system. My wife couldn't tell when it kicked into V4 mode until I told her when it did it.

I too was worried about the V4 noise when I was looking at exhaust systems and I even waited a year before I bought one. So I went with the GM one just because I get deal on it and if GM sells it as an upgrade exhaust it has to be a good system with out any of the problems as a custom exhaust system.

+1

I think we are the only 2 on the site that have it. That is a shame, as it is such a great sounding system.

I wouldn't want any other system now that I have this one.

couple question; How does is sound when towing? And does it mellow out a little more after a while?

And thanks for the write up on this system that made me buy it right away once I say it and found some that sold it to me for under $400!!! Can't get a magnaflow for that and this system is so much better IMO!!

locobill1 · June 23, 2008

I installed the GMPP exhaust yesterday and I really like it. I can very slighly tell the difference in the sound when it drops to V4. It sounds great and is really easy to install.

WestTX.08.Sierra · June 23, 2008

Does anyone have 50 Series Flowmasters? I had these on the Ram that I traded in and I they sounded killer with the HEMI.

WestTX.08.Sierra · June 23, 2008

Nobody has Flows???

aj923 · June 23, 2008

from what i understand flowmasters are outdated tech.. i personally have a magnaflow xl muffler on my 08 sierra.. you can tell when it kicks into 4 cyl mode but you have to really be listening. if your really worried just go to your local muffler shop have them put a flowmaster/magnaflow/dynomax/ect.. in the place of the stock muffler and save the stock one.. if you dont like the way it sounds put the stock one back on..

backwardthreads · June 24, 2008

I have a 40 series flowmaster on my truck. Just had the muffler cut out and replaced with the single out flowmaster, I honestly can't complain about the sound. Yes it does sound a lot different in v4 mode but never enough to make me wish I never had it put on. When mine kicks into v4 mode it sounds like it goes into another gear, but I'm sure it sounds different from the outside. So I like mine.