Rear Grinding Sound/High-Pitch Barely Audible Whine

Sounds a bit like the "carrier bearing growl" on my 97. Seems to be more obvious on vehicles with Trac-Loc because the nature of the groan changes depending on whether the vehicle is turning left or right. Made quite a difference on mine - even when the curve was fairly slight.

The TSB for the 1997 Grand is:

Hey Bill et al,

I guess I failed to mentioned that the whining sound is coming undeniably from the rear.

-Chaud Lapin-

There is a normal sorta high pitched hissing sound from the thing. If someone forgot to add the friction modifier it can get a bit noisier. The hissing sound is sorta metallic in nature, but I sure wouldn't call it a whine, and it isn't that audible unless you are driving in quiet territory. I'd check for a dinged pumpkin, the fluid level, and then pull the cover and see if you have abnormal wear.

Unless of course, your mother-in-law regularly rides in the back seat...

Approximately 11/5/03 22:01, Le Chaud Lapin uttered for posterity:

That hag...she ate all of my Otis Spunkmeyer pastries one day while I ran back into supermarket to get some hot chocolate to go with, so now she rides in the cargo area.

Your "metallic" reference reminded me of two things it sounds like:

1. My father's table saw slowing down from high-rev
2. Boeing 747 turbo's being rev'ed just before take off.

The sound is definitely metallic. Superposed on that is another sound that is more like...

Rorh!...Rorh!...Rorh! - It's speed sensitive and is guaranteed present no matter how long or short the trip.

Finally, I could have sworn I heard a faint remnant of the metallic sound even when the Jeep was standing still, but not sure, will check.

-Chaud Lapin-

Approximately 11/7/03 22:43, Le Chaud Lapin uttered for posterity:

The normal one really isn't that loud, quieter than a normal suv type tire on rain, can't even hear it with the heater fan on at all.

Think I'd ask your vehicle's proctologist to take a look at the rear end.

That would be something else...

---snip---

That sounds like a worn ring and pinion, or a bad axle bearing. Does it get louder when you are going faster or when you increase the load such as going up a hill? "Rorh!...Rorh!...Rorh!" has to be ring and pinion...

Earle

Yeah, the "Rorh!...Rorh!...Rorh!" gets louder and increases in frequency as I get up to highway speeds (55-80). At that point, it's loud and unnerving, but not so loud to as to be unbearable, as if that make sense.

I've never used it to tow anything, and have not paid attention on hills, so don't know. How could this happen? It started when Jeep was less than 3 years old.

-Chaud Lapin-