Rear end noise

[thedude]

I have 97 Tahoe LT 4dr 4wd. A few months ago a whining/humming noise started in my truck. It sounded like I had mud tires on it as loud as it was humming. It wasn't very loud at first and since I was working all the time and damn near broke I ignored it. Now it's super loud so I haven't been driving it. It sounds like it was coming from the front diff. I put it on jacks and ran it to see if i could pin point the noise. Now it's pretty clear the noise is coming from the rear end. The humming starts around 10 mph and increases and decreases with speed. I pulled the drums and dont feel any play around the axle seals up and down and left and right. I also pulled the diff cover and no obvious signs of anything wrong. Th gears dont seem overly worn. The only thing that stood out is the fluid was frothy (bubbly). Thas probably because i had just run it 30 minutes before. Can anyone give me something more specific as to whats wrong? If you need more info just let me know.

 

[Gzes]

Sounds like hub bearings. Have you checked those?

 

[thedude]

I've tried moving them up and down and felt nothing. After i put it on jacks the noise was completely in the rear. There are some issues in the front that have come about at the same time but seem unrelated so i feel the timing is coincidental. I want to take it to a shop and have them check bearings and all but i just dont have the money for that.

 

[thedude]

Just took these. Don't know if they help but I hope they do.

 

[Gzes]

Mine were bad and made loud noise we thought itbwas rear end but did em and fixed the problem.

 

[thedude]

Do you know of a way to check them to see if they're bad?

 

[Gzes]

Lift and like push the wheel left and right and feel for small play.

 

[thedude]

I did that before an figured it was just normal play in the front diff. Thanks for the help.

 

[Gzes]

Np thats what I did in my exploder and thats what it was. Ebay has detroit axle hubs and they are at a good price and good quality

 

[new2yukon]

I also have what I think is a rear end noise. Kind of groaning or growling or like to some extent I am driving on rumble strips. It changes with speed, is there accelerating or decelerating, drive or neutral, forward or reverse, very noticeable when decelerating from around 30mph, tends to be less noticeable around higher speeds-but still present. Figure eights in parking lots will sometimes make it go away, but hard to prove exactly how to quiet it down since it is very persistent noise.

If I am on snow and punch it in 2 high, it seems to go away when the wheels spin and then comes back when slipping stops. Switching in and out of 4wheel makes no difference. If I punch it in four wheel, it is still there since all wheels are gripping. Coasting or neutral makes no difference.

Could not feel any vertical play on front wheels off the ground. Could it be the rear axle bearing? How can I rule out the diff?

Thanks.