Odd Noise During High Acceleration

[MattRobPhoto]

2019 - I installed R&B CAI and the Magna-Flow D-Fit Muffler replacement kit.


When I get on it now, of course I hear the "sucking" of the air into the intake up in the upper left front of the truck of which is to be expected. The truck also sounds much better to me. It's not a lot louder of which is GOOD (for me) but the note is deeper and better (to me).

I've noticed now that when I "hit it" full open... it's all good until I hit about 90mph and then I get this harsh loud buzzing/vibrating type/growling/howling type sound that sounds like it's underneath me. What could this be?

It's hard to explain the sound... it's like all of a sudden, this loud sound happens. It's not high pitched at all, and it doesn't seem to affect the continued acceleration or anything.

My clamps and all are solid tight on the exhaust pipes (from what I can tell) The only "question" I would have in the re-install of the exhaust is where that big coupler is on the driver's side pipe of the two pipes BEFORE going into the muffler. There's that OEM coupler that you have to reconnect and use. It's only on that one side. I'm not CERTAIN that I have the new pipe FULLY seated in there. If it's not, it's very close, so I don't know. Everything else lined up perfectly so it must be in there. it's all tight that's for sure.

Is this fake engine noise??? or do I have some sort of leak? IF so, why at 90mph or so?? OR is this the overwhelming amount of air being sucked it causing this sound????? I don't know, but it's not a good sound to me.

Thoughts?

Thanks!

 

[smurfslayer]

Tires?
Does the sound remain if you stay / cruise at 90 or does it go away if you lift to cruise?

 

[MattRobPhoto]

Oh no it stops after I let off or ease up on the gas.

It’s not tires...

 

[smurfslayer]

that sounds like resonance. if you’re sure nothing on the exhaust is rubbing, or, able to rub another part of the truck, it sounds like you found the drone speed/rpm combo. I used to get a rather awful drone from my 5.0 Mustang with Flowmasters at exactly 68mph and it lasted through 75. It was pretty good at drowning out any other sounds, including music, attempted conversations, the apocalypse, what have you. I swapped mufflers and it was gone.

I have the AWE 2FG (muffler delete) which sounds really good except at about 1100 rpms under some load - like normal mode, 42mph in 10th gear.

 

[MattRobPhoto]

So is that the magna flow muffler that's doing that then???

 

[smurfslayer]

how hard is a swap back to the stock muffler? it sure sounds like it’s resonance from what you’re describing. Any chance you can capture on audio?

 

[MattRobPhoto]

I got back in town tonight jumped in it and drove the crap out of it WITH video and I could NOT get it to do it! Not sure what's up with that, but it wouldn't do it. I tried all kinds of different runs at it. Nothing. I guess that's a good thing. Not sure what's going on....

Regarding the stock muffler: Ya know, those guys on youtube with their PERFECT tools, and PERFECT lifts and all that sure do make it look like it's an EASY ass job to simply remove the muffler.
1. They do NOT tell you about the little tiny metal clips on the stock connections on the TOP where you canNOT see them! 2. They don't tell you about how you have to take the rear tail pipes OFF in order to get the male parts OUT of the female parts. There is no room for movement without taking the two tail pipes all he way off. 3. They don't tell you how difficult it is to get the NEW male end pipes back into the female ends so they are good and seated. Nope. They don't tell you NOR do they illustrate any struggle on their end whatsoever! Nope... it's super easy! 4. Without a lift, without the COMPLETE knowledge of everything it is by far a PAIN IN THE ASS to do! I've done this on my old Silverado and now on this Raptor. I will N E V E R do this again. Never. I don't care if it cost me 500 bucks to pay someone. I'm done with DIY exhaust. Nope. No more for me! Thank you. LOL!

So... NOW... regarding the stock muffler. No. I am not putting that back on. I was so pissed off at that damn thing I threw that big, heavy, ugly bitch in the dumpster!!!

Again, I could not reproduce it tonight. I'll mess more with it tomorrow when deriving, but who knows. I DO think that's what it was though. If I can reproduce it, I will do it and get video/audio footage of it and post.

Any other suggestions on exhaust...? I don't want "loud" I certainly do NOT want "raspy" I don't want drone. I just want a lower note sound with some meat to it. Stock to me, sounds like a rice burner a high school kid tried to soup up for 70 bucks. Ugh...

What about just going QUIET? I don't know. They REALLY need to fix the sound.
Ugh....

 

[GCATX]

Maybe you you ran over some debris and it was hair-lipped in the wind for a few miles, who knows. My front tires need to be replaced soon, they are getting very loud. I notice between 72-75 MPH they seem to set off some resonance vibration in the area of the steering column or dash, pretty high frequency buzzing.

I consider it part of the Raptor mystique, along with the weird shifting sometimes.

 

[smurfslayer]

that reminds me... if the tires were rotated recently you could definitely pick up some extra road noise - a lot. More than I’ve had on other vehicles.

 

[MattRobPhoto]

It's brand new... no tire rotation just yet. So... yea, MAYBE I had something in there somewhere... who knows.

I'm going to be doing some Forscan changes this weekend and driving it a lot so I will keep you posted and we'll see!

Thanks guys!