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Do I Have A Muffler Problem?


Full Member
Nov 17, 2002
I was very excited today, my Assist Steps arrived and I put them on. But while I had it in the garage I noticed a pretty good puddle, then I looked up and found a rather large "spot" on the muffler itself, see picture #2. So my questions are; is the amount of water you see in this picture #1 reasonable? Second, what is the "spot" on picture #2?



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Picture #2 of the "spot"


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I don't like the looks of what you're seeing. Is that a patch we're seeing? It looks like the condensation is coming from a hole at the end of the muffler, but it's hard to tell.
I had my muffler replaced in the first 8 months -no argument from the dealer- after I noticed a vibrating sound coming from the muffler upon acceleration. Made me wonder ....
I'd take it in.
The condensation is normal - I would not worry. As far as the spot looks like a hot spot or discoloration caused by something getting on the muffler like maybe a plastic bag blowing up from the road and melting on and then burning off (sounds strange but I have seen this happen many times). It does not look like a patch at all - if it sounds OK I wouldnt worry. But if it bothers you take it in - they wont replace it just because of the spot though.
I agree with TexAVfan. I think the condesation is going to happen. I noticed this the first month I had my Av. There must be some sort of weap hole in the back of the muffler. You know the catalytic converter spits out water vapor, and all that has to go out the tailpipe somehow. What about the condensation that is still in the muffler when you stop driving? It should come out of the muffler if it can or turn into rust. I've put almost 37K on my Av since Sept. 2001. I don't have any problems with my muffler, just as secure as day 1, and no noise. I'd be more worried about the drive shaft rust. You must have a 2500? There sure is a lot of rust back there.
Thanks for the feedback, we're in the midst of packing things up to move,garage sales, etc., and I saw the underside and thought oh cr*p. I think I'll run in out Monday to be safe and have them check the muffler and the drive shaft rust level. I have a 1500, only had it about a month and a half, but I know it was built in September as I recall.
Yours looks just like mine. I think its normal too.

I discovered mine when I first got my AV. I noticed how nice GM painted everything except for the driveshaft, and rear-end! I was painting them when I saw the brown spot and puddle on mine at that time.
This is totally normal with the stock exhaust. It is a condensation drain hole similar to the one at or near the end of your stock and aftermarket tailpipe tip.

See attached photo.



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Thanks to all for the feedback, and jamie thanks for the photo good to see they look the same.