Consistent Intermittent Whining/Vibration from Front End

[2004Paul]

Hello,

Long time browser, first time post.

I have a 2004 Explorer V8 with 80,000miles. When in 4WD, I get a whining hum noise that get increasing higher in pitch as I accelerate. It only happens at certain RPM and lasts about a second, then 3 or 4 seconds go by, then it comes again for about a second, but only at a higher pitch then the previous. Makes no difference if turning left or right. Shifts good. Once it gets past the third intermittent whine at approx 30 mph, it seems to dissapear. I believe it also does it consistently when slowing down. It is an AWD and it probably has not been in 4WD for a few months. Seems to be coming from Front end or maybe transfer case but wouldn't rule out anywhere else.

I have a 2002 Explorer that always had a noisy rear end, but it was always there if on the pedal...this is completely different.

I've searched for hours and not really finding anything...hoping someone here may have some advice. Thanks in advance

Paul

 

[mbrando1994]

Paul,

Does the noise disappear when the gas pedal is pressed down? Is it a high pitched whine or more of a grindy whine?

 

[2004Paul]

Hi yes, only while accelerating (truck is moving, gas pedal pressed) and yes, maybe closer to an intermittent grinding noise that gets higher in pitch each time as the truck is moving faster. I should also note the transmission is still in first gear when it happens although transmission shifts and is working as expected.

So, as you accelerate slowly, you will hear it 3 times, last for about a 1/2 seconds to a second each time and each time at a higher pitch like if something is grinding it gets higher in pitch as the truck is moving faster all while in first gear on pavement.

I have not tried to accelerate going downhill to know if it disappears (more like it doesn't happen) without the gas pedal being pressed.

Sorry, my explanation is probably not helping my cause