Please help me figure out this sound!!!

This sound has been coming from the front end. Almost sounds like manifold gasket, motor mount, front diff.......? It usually happens at around 1700 rpm and only when I am moving. As soon as I let off the gas it will stop.
http://www.youtube.com/watch?v=qeBkRtSVsLw&feature=youtu.be
Its hard to hear but I dont know what else to do besides go to the dealership and get raped!

 

Anybody?

 

Can't tell from that video. What exactly are you hearing?

 

Weird humming/growl only at around 1500 rpm. As soon as I let off the gas it goes away.

 

I can't tell from the video, but unless it is causing some problem other than just what you are hearing I would not worry about it.

 

Maybe a wheel bearing. I cant ever tell in the videos...

Jack it up and spin the tires to see if there is resistance or grinding

 

I am extremely anal about my truck so I have to figure it out what it is. I dont think its a bearing because I just had to replace the passenger side bearing so I know what it sounds like when one is going bad. Its weird that the sound goes away when I left off the gas?

 

Your video is useless. You need to specify an exact time we can hear the noise. Or make a better video.

When I had weird noises I would stand near the engine and have my wife increase the throttle until I could hear it. Put my hand on it, feel for odd vibration. Sometimes she would give a little gas while in drive with one foot on brake to torque the motor.

I have had the following noises found and fixed:

- Stock 06 air intake tube rattling on side of fender (dealer TSB for air intake)
- fan contacting shroud while in reverse (broken motor mount / Cracked rame)
- idler pulley bearing squeaking (replaced idler pulley)
- l.r. Uca bushings squeaking (installed the spec ride bushings)

 

Can't hear much but it could be a wheel bearing. Try turning left at 1500 RPM and check if the sound amplifies, do the same for except this time steer to the right. This will put stress on the wheel bearings and if it gets louder while steering toward a side, it may just be a bad bearing.

 

wouldnt a front bearing be a little more consistent in making noise other than under throttle at a certain rpm?

 

Yeah thats true it probably isnt a bearing if its going away at >1500rpm but I've had a situation where I had a bad bearing only make noise at around 70 km/h and go away at 90 km/h which was very odd

 

he could probably feel the rim and brake disc for excessive heat, comparing the two sides. when i replaced the bearings in my 89.. i had one making a slight noise.. which developed into extreme heat in about a week. but it was a consistent noise with speed, not with engine RPM.