unusual humming/whining sound

[jgrnot]

I've been hearing a high pithch humming/whining sound for over a year now. Not sure exactly what it is or could be. It almost sounds like it could be rear end related, but it almost sounds like an aerodynamic issue.

When I first noticed the sound, It would only do it about 80 mph (I know, I shouldn't be doing that). The sound has slowly been getting louder and happening over more speeds. Mostly, between 34-42, and 60-65. But, it can be heard slightly from a stop, all the way to freeway speeds. It is more prevelant when accelerating, but it is heard when deccelerating. Can hear it when hitting the brakes. Hear it over the radio.

Hear what I've done in the last year:

I bought a Sirius satelite and put the antenna on the roof. I now this is not causing this sound, I put blue masking tape over it and drove it like normal, the sound was still there.

The windsheild is newer, and the masking tape trick didn't resolve the problem.

New serpentine belt, fuel filter, spark plugs. Don't believe it engine related, sound can't be heard when revving through rpms while tranny's in park or neutral.

I did have a leaking pinion seal. I replaced it on my own, and think I may have over-torqued (or under-torqued) the pinion nut. So I think it could be the bearings in the rear diff. I know I put the right oil and additive in. However, I took it to the best gear and driveline shop in Reno, their head guy didn't seem to think it was related to the driveline. Thought it might be wind over a loose body panel or something. He did say he would like to hear it when I get new tires (they're getting pretty chewed up).

The auto tranny went out just after 100,000K, and the sound was there before this happened.

The driver side CV boot also wore a hole and has been spraying grease in the fender well, and on the side of my truck as well.

I don't think it's the driveshafts and u-joints (no vibrations or extra play), tranny (I hope not), or t-case.

Any ideas guys? I really seem to think I f***ed the rear end up, but I'm lost now

 

[AllanD]

a bad pinion bearing or an ovetightened one will typically make a sound
that almost perfectly mimics the turbine/gearbox noise you hear in the
background if you listen to a helicopter traffic report on the radio...

It a whiney, slightly buzzy, whistling noise.
It is driveshaft speed noise, which is road speed related noise

An axle shaft or carrier bearing is more of a "rumble" and is
a "wheel speed" noise.

AD

 

[jgrnot]

turbine/gearbox noise you hear in the
background if you listen to a helicopter traffic

Is this a high-pitch sound? (or somewhat high)

I just can't recall what this sounds like......read the newspaper, don't watch much news.

The sound has a little similarity to a gas tank skid plate just barely rubbing the driveshaft, kind of a high-pitch hum.

 

[Original_Ranger84]

It might be the transmission if it is a manual because both my 84 ranger and my 07 saturn whine when i get going. but i am not sure what causes it.

 

[Danger-Ranger96]

hmm i've had the same issue before but it may not be the same whining noise, mine was coming from my fan, but it would only whine on hot summer days, the fan clutch can sieze up and cause the sound, maybe if you turn your truck off and try to spin the fan by your hand. If you can't then your fan clutch is probably siezed.

 

[Capt Jay]

I used to have a high pitch whining noise in my truck also. I pulled over and let her out. DONE.

 

[skippy]

I used to have a high pitch whining noise in my truck also. I pulled over and let her out. DONE.

thats good!

 

[Apollo]

i heard a high pitch whining sound in my cousins 87 b2 when i borrowed it for 2 years and one day i went threw a intersection and kaboom, the rear end ended up in a million pieces. replaced the rear end and the noise was gone.