Ford Escape: Harmonic resonance under acceleration? VIDEO/audio

[pyro]

Check out the video below. Anyone in the automotive field heard this before?
Mind you, this vehicle is a 1st year edition ('01) with 168,000 miles on it.
It makes sounds like musical fifths and otave tones under acceleration, you can hear it in the video. Anything more than 2/3 throttle and it will do it. This vehicle has also experienced sporadic shudder upon converter lockup under gentle acceleration, and mild shudder upon "unlock" during passing maneuvers at highway speeds.
The fact that the pitch or its harmonic stays constant tells me that maybe it's resonating the stall RPM of the converter?

(the slip at the beginning is wheel spin, not "slip" slip )

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[pyro]

ttt...

[jtaj77]

Does this truck have a noise canceling system?

[pyro]

wtf??? It's a drivetrain noise, not a sound system issue...

[jtaj77]

wtf??? It's a drivetrain noise, not a sound system issue...

Our cars with noise canceling make some strange noises when they have problems with engine mounts, some of ours are electronic mounts, or they have an issue with the noise canceling unit it's self.

[allstock]

Is it AWD or FWD? A torque converter shudder can become a constant "resonance" sound if the conditions are right. Certain speed,throttle opening,grade,temp etc. If it's AWD I have seen the universal joints in the driveshaft that goes to the rear differential cause all sorts of weird complaints as well, the ONLY way to check them properly is to REMOVE the shaft and check them. That shaft i have also had to send out for a high-speed balance to correct various complaints as well. I have also seen bad engine/transaxle mounts cause complaints as well. If it's AWD you HAVE to have four IDENTICAL tires on it,type,brand,size,amount of wear, all of it. A difference 1/16" in height is MAX.

[pyro]

Thanks for the notes.

It's automatic 4WD. It's fun to drive in the winter.
It goes whatever direction you turn the wheel, no matter how fast the wheels are spinning on the slick stuff or how far sideways it's drifting.

The noise only presents itself under 1/2 throttle or more pedal while accelerating.

[joed]

Bud on any American made piece after 1000000 mile you have to turn the sterio up so as not to hear these things. Sound like its been a good one.