Squeak in 4 cylinder mode

[Centex14]

What the heck is this annoying squeaking when in 4cyl mode and how do I get rid of it or dampen it until I get it tuned?

 

 

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[GrumpyAeroGuy]

Probably the exhaust flapper valve. Search on that. I know I have read numerous posts on that here, and what folks have done to eradicate it.

Mine does it too...just doesn't annoy me that much...

It actually helps me detect the 8 to 4 cyl switch, as it is otherwise undetectable on these new trucks.

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[tbarn]

X2 on the flapper valve.

[bc-chris]

x3 on flapper valve!

 

[Jonty711]

X4 on the flapper valve. Best thing would be to wire it open and confirm the noise has disappeared 

[Sierra Dan]

Final answer,  the exhaust adaptive ( aka Flapper Valve)

Mine did the same thing and is now clamped open when switching from V4 back to V8 and also on warm startup.

Some have luck with a dealer replacing the entire exhaust under warranty.

[Centex14]

Found the flapper.  It's shot.  Hardly any tension on the spring at all.  Stuck a nail through it to hold it until I run by the store and get a hose clamp.  Now that I think about it, I might just bust out the welder and fix it permanently.

[Sierra Dan]

  Now you're talking!

4 hours ago, Centex14 said:

Found the flapper.  It's shot.  Hardly any tension on the spring at all.  Stuck a nail through it to hold it until I run by the store and get a hose clamp.  Now that I think about it, I might just bust out the welder and fix it permanently.

 

[Jonty711]

There is a technical service bulletin on this. You should be able to get the dealer to swap it out easy enough, before you take the welder to it. 

[Centex14]

It would take me more time to call the dealer than it would to throw a bead on it and never worry about it again. I put a 100 miles on the truck today with no issues so whatever that valve is for it’s obviously not important. Dumbass design. At least the valves on my charger are electrically operated. Cost me a $150 to bypass them and not throw a light but at least it’s a decent design.


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[Jonty711]

15 minutes ago, Centex14 said:

It would take me more time to call the dealer than it would to throw a bead on it and never worry about it again. I put a 100 miles on the truck today with no issues so whatever that valve is for it’s obviously not important. Dumbass design. At least the valves on my charger are electrically operated. Cost me a $150 to bypass them and not throw a light but at least it’s a decent design.


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I get ya. I couldn’t stand the 4cyl drone though in mine 

[Centex14]

There was no drone in mine today. Hell I can’t hear the Borla exhaust on the truck because it’s so quiet.


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[Sierra Dan]

No drone with mine clamped open.

Has a nice subtle rumble at startup.