Hi everyone,
Since I bought my 01 a few months back it's has a howl or whine coming from the rear of the jeep. Dealer tried to tell me tires but the sound doesn't change regardless of pavement type or on rain and snow. Starts to be noticeable at about 20 mph. I assumed rear wheel bearings and replaced them. Everything inside the diff looked good but I'm no expert. Unfortunately it wasn't the wheel bearings.
Anyone have any suggestions? I rotated the tires and noise remained in the rear.
Thanks!

 

is it like a rubbing sound....kinda like something rubbing?

 

i was figuring the u joints as well.... ah, could be in the breaks. could be in the drive shaft. is there any play in rear shaft? and are you POSITIVE its coming from the rear?

 

it could be that you are low on dif fluid. happend to me in my bmw. then came vibrations then came a loud boom! and i couldnt move.

 

damn, that sucks. what model beemer? was it a pricey fix, or is that why you own a jeep now. haha.

 

93 bmw 318is m3 replica still sportin the m42 4 cyl with individual throttle bodies lol. was a 500 dollar fix in my back yard lol. i still have it. im selling it soon. to get another xj

 

I know the diff fluid is ok because it was doing it before and after I changed rear wheel bearings. It's definitely coming from the rear. Someone else told me could be u-joints. Could you check play by using your hand? how much play is acceptable? Thanks for the help.

 

Ring and pinion maybe?

 

Yes you use your hand. There shouldn't be any play in u-joints.

 

IF YOU HAVE A CONSISTANT WHINE IT IS QUITE POSSIBLY A PINION BRG THAT IS FAILING. Jack up the jeep, remove rear wheels and brake drums, unbolt rear driveshaft and rotate the yoke, see if you can feel/hear anything. It should rotate with a small amount of drag, but smoothly.
Good luck

 

Thanks for the advice. I'll try that next.

 

Thanks Renix I'll try that when I check the pinion bearing.

 

I had a whine/howl come from the rear awhile back, it turned out to be some broken crap in the rear diff. When I checked the fluid it was black and had metal glitter all in it. I had to get a new axel which I found used for $150.

 

Sounds like your ring and pinion is your culprit. Although if it's only a slight howl chances are it will be fine, but if it starts to get louder with time then you will need to change them out as you will start to loose teeth from the ring or pinion gear!

Is it more noticeable when you let off the gas???

 

my pinion bearing is going out due to water getting in the diff, and it is extrememly loud, you can only hear it when gas is applied and the yoke has slight movement. shop wanted 280 to replace it so i said naww and got a dana 44 for 150 so the 8.25 is outta thereee.