Exhaust Issue...

[Trav_13]

My 09 Sierra with the 5.3 Flex Fuel LMG has an exhaust leak that I have not been able to track down since day 1.....I got the truck with 800 miles on it, and noticed it right away, however I drove it for a couple thousand miles and thought well maybe its something with the factory exhaust...i'm going to put my aftermarket exhaust on anyway, so I'm not going to worry about it....anyway long story short...I've had the truck a year now..it has 14K miles on it...aftermarket exhaust has been on for 12K miles, and I just got around to taking it in for warranty...

 

I talked to my buddy who is the technician and he couldn't seem to find anything near the exhaust manifold gasket, exhaust manifold, or the exhaust (donut) seal...he did come up with a bulletin 10-06-05-003 which is to replace the clamp behind the convertor on the exhaust system...so anyway we had that done yesterday, and NO GOOD...I am still hearing the small exhaust leak which isn't horrible,but it's not acceptable for a $40K truck....the noise sounds like it right at my feet, however I crawled underneath the truck this am when it was running to see if I could see or feel anything...and I can't find anything, but that damn noise is still there....this noise seems to be noticed when the truck is under light acceleration, and it doesn't matter if it is warm or cold...does anyone have any suggestions worth looking at before we start tossing parts at it...

[Julien]

On my 09 I had an exhaust leak from day one and it was the clamp behind the cat, did you double check that clamp, even with a new clamp if the 2 flanges are not lined up properly it still leaks, just a suggestion.

[Trav_13]

On my 09 I had an exhaust leak from day one and it was the clamp behind the cat, did you double check that clamp, even with a new clamp if the 2 flanges are not lined up properly it still leaks, just a suggestion.

 

I'll have to check it out....if it wasn't in warranty still I'd just have that clamp removed and have them weld the pipes together...I have aftermarket exhaust anyway...I wish they still bolted up from the catback like they did in the old days!

[Prokopchuk_9]

i dont know about the new ones but mine the clamps behind the cats were JUNK. id make sure they are aligned perfectly man

[Trav_13]

Does this look like it has the potential to leak? Seems to not be aligned properly if you ask me...

 

 

 

And what does this thing do...is this a resonator of some sorts to help with the V4 to V8 Switching??

 

[BigBlueLB756]

Clamp looks nice and shiney!

[Trav_13]

Clamp looks nice and shiney!

 

Yeah, its only got about 10 miles on it.....

[youcantkeepup!]

That flex pipe looks like it has pin holes in it, look at the carbon on the wire mesh

[Trav_13]

That flex pipe looks like it has pin holes in it, look at the carbon on the wire mesh

 

 

Good Call...I will check this out to...that may be very possible....didn't even realize that in all the time I have looked at it....

[wfleeger]

That flex pipe looks like it has pin holes in it, look at the carbon on the wire mesh

 

What the heck is that thing??

[Trav_13]

That flex pipe looks like it has pin holes in it, look at the carbon on the wire mesh

 

What the heck is that thing??

 

 

 

Trying to figure that out myself....I'm hoping I don't need it, and can delete it all together by putting a piece of pipe in there?