Chrysler 300M Enthusiasts Club
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  • Talk about the most common LH mod, and why Chrysler didn't do it.
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Talk about the most common LH mod, and why Chrysler didn't do it.

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 #388072  by Shatner64
Greetings all!

A few years ago, I purchased a reasonably priced 2003 300M Special in Graphite Metallic for my daily driver/commuter. It has proven to be a comfortable, stylish, and economical car. As a testament to it's styling, many people often think it's a new car, and not 18 years old! Needless to say, I'm happy with my purchase. :)

One thing that has struck me as odd, though, is how quiet my exhaust seems to be when compared to other stock 300M Specials. My friend's Dad, for instance, has a 2002 with about 40 000 Kms on it, and it sounds very aggressive. I suspect the previous owner of my car had swapped to a quieter muffler at some point, but I'm not sure.

I crawled underneath the car, and took a picture of the numbers on the muffler (attached). Does anyone know if this is, in fact, the factory muffler for this car?

If not, does anyone know the part number for it?

Thanks so much! :)

P.S. The numbers on my muffler are as follows:

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 #388081  by Sneke_Eyez
Welcome to the Club, Kevin!

I cannot tell you based on the part numbers, but the 300M had a very unique rear resonator for the LH car line. It was the only LH car with the single-in, dual out exhaust style like that resonator. If you have dual exit exhaust (hard to tell from the picture), you've got the right muffler back there. It would not have been possible to swap to another Chrysler part that would fit there.

Now there are things you can do to "wake up" the exhaust a bit, including removing the rearmost resonators. Many discussions of exhaust modifications are here on the forums.
 #388087  by Shatner64
Thanks for the quick reply!

Yes, I do indeed have the dual outlet exhaust. I'm still puzzled, though, as to why mine seems so much quieter than others I've heard. There's none of those lovely crackles and pops that I've heard from other cars. But, if that's the only muffler that will fit this exhaust, it must be the stock one. *shrugs*
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 #388097  by LUNAT1C
Correct, this is the only Chrysler-supplied muffler for this application, and since you have a Chrysler part number and presumably no evidence of the exhaust being tampered with (pipes cut and welded), I would venture to say your system is 100% as it was when it left Brampton. That assumes your front resonator and two rear resonators are also the factory units.

I wouldn't think anything of it. Every car is different. My factory exhaust note sold the car to me the first time I started it at the dealership, with the door open. Since then I've modified it to increase the tone and now I'm looking at further upgrades since I found my front resonator is splitting.

Chrysler used a transverse muffler for the Special, which is also available in the aftermarket for any desired upgrades. I believe Flowmaster and Magnaflow also produce transverse mufflers (mainly for the 4th generation F-Body Camaro/Firebird group).
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 #388100  by FIREM
Many "Special" owners over the years have reported "White Angle Hair" coming out of their dual exhaust tips. (Haven't heard of this on a "Base M")
It is suspected to be packing from the the transverse muffler. This would change the exhaust note without a doubt.
Maybe your friends dads has shed some hair and ours has not. Maybe some "spirited driving" could loosen some up, worth a shot before cutting into that exhaust system.
 #388141  by Shatner64
Hmmm, hard to say. I did drive my friend's Dad's car home from the dealership when it was new, and I swear it was much more aggressive-sounding.

I recently found a Special exhaust for sale on Kijiji. Interestingly, the part numbers on that one do not match those found on mine. Both mufflers have the Pentastar stamped on them. The mystery deepens!
 #388173  by Countachqv
In regards to the first upstram resonator/muffler the special has a 2 ins 2 outs. Which magnaflow model works? the 12468 18" length 2.5" or 11385 14" length 2.25".
I screwed up and ordered the wrong one 12258. Thanks for any quick reply that confirms
 #388174  by PunisherM
When mine rotted out I just replaced it with straight pipe