E350 Droning noise

[REDOVAL]

Just another thought, but driveline noises relative to load or throttle application have unique signatures. I have a Ranger that lost pinion preload in the rear end and it makes all sorts of racket under trailing throttle at high speeds...nothing anywhere else. I wouldn't discount worn gears or rear end parts.

Also, my cat was stolen years ago and I drove for 2 years with a straight pipe with zero drone. I do have a flowmaster 70 series muffler which also doesn't drone (all of this on a v10).

Scott

[mjcleland]

Talked to a Ford Tech about removing the resonator from the 7.3 intake. He advised against it as the resonator was there to defeat a harmonic drone. I suspect your custom intake did not leave a resonator in place?

Could be the issue with the noise.

[REF]

Pull the doghouse and check the clearance of the exhaust against the doghouse opening or for any other contact with anything, that will certainly make a racket. Is it a stock exhaust? Not just the muffler, but larger pipes?
I’ve got very little clearance with my 4” pipes from the turbo on the 7.3, I had some work done where the exhaust flange clamp at the turbo had been loosened up and I noticed a droning afterwards. Once the pipe had heated up and expanded from driving, it made contact with the metal pinch seam along the doghouse opening that created an unusual amplified sounding drone at just the right resonance, I had to loosen the flange clamp and pry the exhaust away just enough from making contact before retightening things. Check clearance and signs of any exhaust contact

[TCNorthwest]

Originally Posted by REF

Pull the doghouse and check the clearance of the exhaust against the doghouse opening or for any other contact with anything, that will certainly make a racket. Is it a stock exhaust? Not just the muffler, but larger pipes?
I’ve got very little clearance with my 4” pipes from the turbo on the 7.3, I had some work done where the exhaust flange clamp at the turbo had been loosened up and I noticed a droning afterwards. Once the pipe had heated up and expanded from driving, it made contact with the metal pinch seam along the doghouse opening that created an unusual amplified sounding drone at just the right resonance, I had to loosen the flange clamp and pry the exhaust away just enough from making contact before retightening things. Check clearance and signs of any exhaust contact

Do you have any pictures of your down pipe with the doghouse off?

[HIGHCOUNTRYMIKE]

Twoxentrix,
This is a Hail Mary & will sound crazy.
Your "Hail Mary" just won the Super Bowl in my mind, nor is your suggestion crazy.
I just returned from a High Sierra test drive to evaluate my new rear shocks. Overnighter to Bishop.
On the way back near Lone Pine I started to hear this trip ending noise from the "engine compartment". Stopped checked engine and under carriage. No visible issues. All 3 engine gauges were reading normal.
Noise starts at 40 mph. Noise increases as speed increased. When I stopped and tested engine in neutral all was normal (7.3 with 288,000 miles).
As soon as I arrived home I went online to post this report and wait for ideas on how the approach the solution. I read This is a Hail Mary & will sound crazy. I immediately went outside and looked at my window (which was installed last week). The entire top window molding has pulled loose.
Problem solved. Tomorrow morning I shall visit the installer for a repair.
Thank you "Twoxentrix" and thank you "Sportsmobile Forum"
HIGHCOUNTRYMIKE 2003 E350 EB 7.3 SMB 288,000 miles

[Twoxentrix]

Ha, Glad then i put that suggestion out there. I have to say, the noise I heard was exactly as you mentioned - from the engine compartment/transmission area...I would never have even considered looking anywhere else (none of us did), especially the windshield! Had us all stumped if it wasn't for the one person that made the comment...so in this instance I'm glad I managed to be "that guy".

[JWA]

Sorry for being late to this thread but as I'm in the windshield business AND this same thing has happened to me on my own 2003 E-250 after *I* installed a so-called premium windshield its humorous by only after the fact.

The surround molding has a metal spline that makes it quite rigid and sadly that part commonly comes loose causing a tremendous racket. Mine was loud enough it drowned the radio out while on 120 mile return home trip.

These days when we install moldings like these, those that come as part of the windshield "back filling" with the adhesive we use tends to completely eliminate this as a future issue. It can and does happen with any vehicle where the moldings are designed to be caught or trapped by the applied adhesive---its become a common practice "back filling" these days.

Glad this was nothing more----humorous after the fact as I say.

[HIGHCOUNTRYMIKE]

The humorous part was having placed the problem in the engine compartment.
When I took my van to have the molding repaired I watched the installer.
He completely "back filled" the entire molding. There was excess squirting out from under the molding. After pressing down and scraping off the excess he completely cleaned the molding and van body around the molding.
I was very pleased with the amount of sealant he used.
I hope that will prevent the molding from coming lose in the future.
It all seems like a bad dream now.
2003 Ford E350 SMB 4X4, 7.3 HighCountryMike

[ctb]

Last/late suggestion/question...New tires right? Could one have a 'bad belt' on one of them? I bought new tires for one MDX and upon picking up and driving home the faster I drove (HWY home) the louder the sound became...let off gas, sound lowered....took it back to COSTCO and they stated that I had a bad/defect tire/radial belt (probably)...they replaced my front left tire and the sound has gone away....just a thought