June 25, 2018, 04:00:05 AM

Author Topic: What’s with the indentation on the GM mufflers?  (Read 2341 times)

Offline Barn Owl

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What’s with the indentation on the GM mufflers?
« on: June 24, 2007, 08:10:58 PM »
I have had this question ever since I opened the tailgate on my bus: Why do the GM’s have an indentation on the backside of their mufflers? It doesn’t seem to be there for any clearance issues. I don’t know how many models used them, but I have seen them on the 4106s and 4107s.

Just want to know.

Laryn
L. Christley - W3EYE Amateur Extra
Blue Ridge Mountains, S.W. Virginia
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Offline NCbob

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Re: What’s with the indentation on the GM mufflers?
« Reply #1 on: June 25, 2007, 06:29:41 PM »
You can't imagine how I honestly tried to balance the ying and yang of this question before bringing myself to ask one myself........

Could it be the result of the push starts from MCI's?

Egads! Am I ever going to get flamed for that one!

Bob
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Offline FloridaCliff

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Re: What’s with the indentation on the GM mufflers?
« Reply #2 on: June 25, 2007, 06:37:31 PM »
Bob,

You better be sleeping with one eye open!!!!!!!!   8)

I thought you would be over that GM jealousy by now...LOL   ;D

Remember as I said the other day " the only thing that could be improved on your MCI-5 was if it had a GMC emblem"    :-*   :-*   :-*

Cliff





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Re: What’s with the indentation on the GM mufflers?
« Reply #3 on: June 25, 2007, 07:04:35 PM »
Bob,

Keep Your GM ALL GM!

Offline kyle4501

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Re: What’s with the indentation on the GM mufflers?
« Reply #4 on: June 25, 2007, 07:44:09 PM »
Ole Bob is just jealous of GM's.

I'll bet he really wants a scenicruiser  ;D
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Offline Utahclaimjumper

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Re: What’s with the indentation on the GM mufflers?
« Reply #5 on: June 25, 2007, 07:48:17 PM »
I went out and checked my 06 muffler. no indentations, perfect cylinder top to bottom.>>>Dan
Utclmjmpr 
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Offline superpickle

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Re: What’s with the indentation on the GM mufflers?
« Reply #6 on: June 25, 2007, 08:14:50 PM »
 :)........... :).............. Please continue the petty bickering ...... ;D
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Drive an SUV.

Offline kyle4501

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Re: What’s with the indentation on the GM mufflers?
« Reply #7 on: June 25, 2007, 08:35:54 PM »
Hey Bob, if mci's are so great, how did all the GMC's get in front?

 ;D  ;D  ;D
Life is all about finding people who are your kind of crazy

Get your facts first, then you can distort them as you please (Mark Twain)

Education costs money.  But then so does ignorance. (Sir Claus Moser)

Offline RJ

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Re: What’s with the indentation on the GM mufflers?
« Reply #8 on: June 25, 2007, 11:13:33 PM »

Hey Bob, if mci's are so great, how did all the GMC's get in front?
 


Easy, Kyle - alphabetical   :D :D :D :D
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Offline kyle4501

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Re: What’s with the indentation on the GM mufflers?
« Reply #9 on: June 26, 2007, 06:44:02 AM »
Easy, Kyle - alphabetical   :D :D :D :D

Waht if yuor'e dyslexic?

BTW Bob's in NC, are you sure he can spell?  ;D ;D
Life is all about finding people who are your kind of crazy

Get your facts first, then you can distort them as you please (Mark Twain)

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Offline uncle ned

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Re: What’s with the indentation on the GM mufflers?
« Reply #10 on: June 26, 2007, 06:47:26 AM »

    Looked at the muffler on my 04, no indention but kept looking up it and found a couple old mci's. cleaned them out and cured my heating problems. been hunting that problem for years.

uncle ned
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Re: What’s with the indentation on the GM mufflers?
« Reply #11 on: June 26, 2007, 07:58:08 AM »
My 2¢.....

I think the indentation is from some mechanic sitting down there banging his head and trying to figure out what the previous guy did to get it into this condition.


Offline Hi yo silver

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Re: What’s with the indentation on the GM mufflers?
« Reply #12 on: June 26, 2007, 12:52:04 PM »
Ya See, Laryn...
I told ya there were lots of helpful and intelligent guys on this board! ...I'm sitting here grinning and shaking my head...he! he!
Blue Ridge Mountains of VA   Hi Yo Silver! MC9 Gone, not forgotten

Offline Buffalo SpaceShip

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Re: What’s with the indentation on the GM mufflers?
« Reply #13 on: June 26, 2007, 02:36:11 PM »
Laryn... OK, seriously. My old '06 did not have "the dent" and my current '08's is so far up and back behind the engine I'd never know if it did, but I have seen my fair share of "dented" ones in pics that it must have been an option or factory alteration at some point. Maybe to provide clearance for lid actuators or something.

There's a few GMC buses on eBay right now that indeed have "the dent".

FWIW,
Brian B.
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Longmont, CO

Offline Barn Owl

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Re: What’s with the indentation on the GM mufflers?
« Reply #14 on: June 26, 2007, 08:54:07 PM »
I think the ones without the dent are not OEM mufflers. My manual shows the dent. I have seen a few without, but thats not the norm for what I have seen. Your right, I've been thinking too hard! :P
L. Christley - W3EYE Amateur Extra
Blue Ridge Mountains, S.W. Virginia
It’s the education gained, and the ability to apply, and share, what we learn.
Have fun, be great, that way you have Great Fun!