[Frosty]

Sorry for some of the recent random questions. I'm just gradually going down my list of possible concerns with my car in an effort to make it right and my exhaust is next on the list. I had once thought it just had an exhaust leak at the flanges in front of the cats but I couldn't locate one after throwing it up on my lift and listening/feeling around all the joints. If needed I can smoke test the exhaust system to double check but normally something this loud is obvious. As such it got me wondering, is this noise normal? I don't recall the cars I test drove besides this one sounding this way but my attention may not have been sparked on it at the time of those test drives.

From what it sounds like it's noises coming from the cats which seems odd since their aren't movable parts in there. It's not super bad at idle but pretty noticeable but when accelerating it sounds pretty bad.

Any thoughts on the below video? Sorry for the sideways view. I tried to take the video in the correct fashion but I guess it turned on me when I reached under the car. In person the sound is louder than what the video picks up but not by a huge margin.

Also, according to the carfax the cat recall was done right before the car was traded in.

 

[Slowpoke387]

I hear nothing unusual at all.

 

[DGatzby]

If you believe you hear things in those converters, have a look. They may have broken down inside. When they do that, multiple chunks of “stuff” that resemble charcoal are busted and floating around inside with assorted insulation particles. If it gets real bad you will get a check engine light and probably a P0420 code. They can be blown apart inside with some aggressive driving.

 

[Howjta]

I have the same noise and it drives me crazy. It is really hard to get on video but it sounds like an exhaust leak. Mine will go away if the car is at operating temp and very loud when cold. My friend has a 16 hellcat as well and it’s much quieter. I have not done cat recall on mine. Wonder if it would be worth it

 

[Himmelkat]

I have not done cat recall on mine. Wonder if it would be worth it

Do you like your tailpipes to be sticking out weirdly different distances with the dealer squirming out of any responsibility and Dodge telling you to attempt self-impregnation when you show the photo-documented evidence that it was not that way before you brought it in?
Then yes, get the recall.

 

[36Grizzly]

Do you like your tailpipes to be sticking out weirdly different distances with the dealer squirming out of any responsibility and Dodge telling you to attempt self-impregnation when you show the photo-documented evidence that it was not that way before you brought it in?
Then yes, get the recall.

Ok so it's not just me then. My dealer did the cat recall on my recently purchased 2016 HC prior to me taking delivery. Both of my exhaust tips now look like they are pushed forward and under the bumper a bit more than I remember on my old Scat Pack.

 

[Frosty]

I think it's the opposite that occurs to where they stick out further.

This begs the question. Are there any good street legal bolt in cat kits for sale? Maybe some with the green kooks cats? I see them for header kits but not factory replacements.

 

[Howjta]

I know I have seen a few options for catted midpipes but they are not cheap. I guess for anyone who has also done the recall, they update PCM as well correct? Has anyone seen any positive or negatives with new cats and PCM update? Or anything noticeably different.

 

[Rockster]

Hear a bit more noise from the driver's side vs. the passenger side.

Hard to say where it is coming from.

Best advice I can offer is get the car on a lift and with the engine running use a stethoscope to try to pinpoint where the noise is coming from. Accessory drive. Engine. Exhaust.

While it is true the converter has no moving parts I had a converter "brick" break loose. This arose when the converter was hit by some road debris -- big chunk of a cinder block -- the impact severe enough to put a substantial gouge in the converter housing. But the impact also caused the converter brick to come loose. As a result for a long time every once in a while the CEL would come on with an error code indicating a converter -- the one hit -- operating below efficiency.

I'd read the code then clear it and the CEL would stay off sometimes for months. The car passed several CA smog checks with no issues.

Then the buzzing when the exhaust was up to temperature appeared. This was bad enough then I started hearing a low dull knocking sound when I started the cold engine.

At some point the noises became intolerable and I went to a business that specialized in salvaging parts for the model of car I owned and bought a pair of used converters. These sold for half the price the factory wanted for new converters. At the dealer the tech swapped out the old converters for the "new" ones. Noise gone. And the "new" converters operated correctly and smog testing was not a problem.

 

[pitbullbob]

I know I have seen a few options for catted midpipes but they are not cheap. I guess for anyone who has also done the recall, they update PCM as well correct? Has anyone seen any positive or negatives with new cats and PCM update? Or anything noticeably different.
[/QUOT
Howjta i did the recall 2016 hellcat m6 car see.s to run fine no belive it was detuned but cold start less agressive and over all exghast note seems little quieter as if active exghast is not the same and when i shut off in my garage i hear low muffled belching sound for couple seconds ?

 

[Himmelkat]

If you believe you hear things in those converters, have a look. They may have broken down inside. When they do that, multiple chunks of “stuff” that resemble charcoal are busted and floating around inside with assorted insulation particles. If it gets real bad you will get a check engine light and probably a P0420 code. They can be blown apart inside with some aggressive driving.

If you have access to one, shove a lit snake light up the tailpipe with the exhaust valves locked open and take a gander at the cats from the back side.

 

[DGatzby]

If you have access to one, shove a lit snake light up the tailpipe with the exhaust valves locked open and take a gander at the cats from the back side.

That could work, except the screen in the rear was intact and was restricting it from discharging any of the broken pieces.

 

[Himmelkat]

Looks crummy.

 

[DGatzby]

Looks crummy.

It cost Dodge a HO engine, SC, oil cooler and converters. They stood by their product and I continue as a very happy customer and will keep doing us proud at events some say we can’t do well at.

 

[pitbullbob]

It cost Dodge a HO engine, SC, oil cooler and converters. They stood by their product and I continue as a very happy customer and will keep doing us proud at events some say we can’t do well at.

Hey Dgatzby i have 3 srt challangers srt8 hellcat and demon the company has taken care of me on each one .i was orginally concerned about my recent recall on hellcat but know it seem s to be working out and ok . When i bought hellcat brand new in 2016 .(bought in febuary buffalo ny winter.) Had it flat bedded to my garage .didnt get first ride in till april 15th . Wife and i took 40 mile ride never went over 55 60 did and prepared to do proper break in . Long story short pulled in to destination shut off got out to swimming pool of antifreeze. Popped hood no hoses blow off under close inspection blew off out of over flow on secondary cooling system . Never overheated lost alot from tank. Eventually drove back home shut off and it erupted again . My first thought headgasket.( not leaking externally) Back on flat bed to dealer. I know them there got call few hrs later
The did hydro carbon test motor full of antifreeze company insisted pull motor and they give me new one .or i can start with new heads and take it from there .( cracked aluminum head) but they say we prefere you take new engine they'll make good . I went with new motor and paper work to keep with title .( non matching#) they sent motor out right away sc. clutch pack complete . They made 2 full car payments and bought me 350.oo cover . The re ent recall cats o2 flash was first time it went back for anything. ( i do my own oil changes) the company backed me and i dig all my cars. Just backing what you said.

 

[DGatzby]

Hey Dgatzby i have 3 srt challangers srt8 hellcat and demon the company has taken care of me on each one .i was orginally concerned about my recent recall on hellcat but know it seem s to be working out and ok . When i bought hellcat brand new in 2016 .(bought in febuary buffalo ny winter.) Had it flat bedded to my garage .didnt get first ride in till april 15th . Wife and i took 40 mile ride never went over 55 60 did and prepared to do proper break in . Long story short pulled in to destination shut off got out to swimming pool of antifreeze. Popped hood no hoses blow off under close inspection blew off out of over flow on secondary cooling system . Never overheated lost alot from tank. Eventually drove back home shut off and it erupted again . My first thought headgasket.( not leaking externally) Back on flat bed to dealer. I know them there got call few hrs later
The did hydro carbon test motor full of antifreeze company insisted pull motor and they give me new one .or i can start with new heads and take it from there .( cracked aluminum head) but they say we prefere you take new engine they'll make good . I went with new motor and paper work to keep with title .( non matching#) they sent motor out right away sc. clutch pack complete . They made 2 full car payments and bought me 350.oo cover . The re ent recall cats o2 flash was first time it went back for anything. ( i do my own oil changes) the company backed me and i dig all my cars. Just backing what you said.

That is more great stories! You know it starts at your local dealer. I bet you have a great relationship with them too.

My original engine ate two superchargers before the last one emptied most of its steel filings into the combustion chambers before it came to a seized rest. We do believe it had a bad converter for a long time. I’ll give them credit, they knew the car was on a closed course (NOT IN COMPETITION) and honored that warranty more than once now. My Service Managers and Advisors all have my YouTube Channel address. I actually encourage them to test drive my car when they are done, not discourage it because they may abuse it. The tech who does most of the important wrenching on mine has my phone number and trades texts about the car! Hell if you abuse it too much on the street you get to go to jail anyway. They can’t run it any harder than I do on a road course and they know it. He was funny last week. He told me he got the tires to spin. They are big 345/30’s. But as we all know that don’t matter to these beasts of torque. Ha, told him that was not very impressive!

 

[pitbullbob]

That is more great stories! You know it starts at your local dealer. I bet you have a great relationship with them too.

My original engine ate two superchargers before the last one emptied most of its steel filings into the combustion chambers before it came to a seized rest. We do believe it had a bad converter for a long time. I’ll give them credit, they knew the car was on a closed course (NOT IN COMPETITION) and honored that warranty more than once now. My Service Managers and Advisors all have my YouTube Channel address. I actually encourage them to test drive my car when they are done, not discourage it because they may abuse it. The tech who does most of the important wrenching on mine has my phone number and trades texts about the car! Hell if you abuse it too much on the street you get to go to jail anyway. They can’t run it any harder than I do on a road course and they know it. He was funny last week. He told me he got the tires to spin. They are big 345/30’s. But as we all know that don’t matter to these beasts of torque. Ha, told him that was not very impressive!

Yes iam know at the dealership were the hellcat came from . I know the teck who replaced engine and did my recall work . He drove both times . If he payed with it it wasn't to badley he wouldn't want to have to be responsible if something stupid happened.my srt8 chally came from differet dealer i dont go there.never had any real.problems with it .my be oil pressure sensor wich was common and evaporator tank. I do oil. Demon came out off tennesee . Velociy motor cars check them out online.

 

[Xylander]

There's another easy way to see if the catalyst has fractured. Simply crawl under the car and smack it with a rubber mallet. Listen for marbles.

 

[DGatzby]

There's another easy way to see if the catalyst has fractured. Simply crawl under the car and smack it with a rubber mallet. Listen for marbles.

Darn it, I wish I would have done that to hear it so that never happens again! Thanks for the tip, I will be tapping and listening to them whenever I am under it now.

 

[Pitbullduke61]

I have the same noise and it drives me crazy. It is really hard to get on video but it sounds like an exhaust leak. Mine will go away if the car is at operating temp and very loud when cold. My friend has a 16 hellcat as well and it’s much quieter. I have not done cat recall on mine. Wonder if it would be worth it

Hey was wondering your friend had the cat recall on his 2016 hellcat . You say its quieter hellcat since he did recall did he also notice power loss ? I had my 2016 challanger m6 cat recall and my car is also quieter but i also notice some power loss.