I noticed a loud squeal coming from the left front wheel area while slowly backing out of the garage recently. This happens for only a short time (about 10 feet) just after backing out, then goes away. It happens every morning after the Jeep sat all night. I jacked up the left front and rotated the wheel, first counter-clockwise (forward) with no sound, then clockwise (reverse) which caused a loud squeal. The squeal is loud and sounds like a brake pad wear indicator. It only happens when I rotate the wheel clockwise (as in reverse) or when backing out of the garage. I checked the pads (like new without excessive wear), the pad wear indicator (it's not touching the rotor), the pad retaining clips (not loose), and the splash shield not touching the rotor. The squeal is coming from the brake area but I cannot find it. I even removed the wheel and checked everything again and it still squeals when the lug nut flange is rotated aft (reverse only). It always goes away when driving forward and squeals only when in reverse and only from the left front wheel. When I wash the Jeep's wheels, I always flush out the brake dust in and around the caliper with a hose to eliminate buildup. Not sure if this practice contributed to the recent noise.
Any suggestions?

 

Any chance it could be a rock stuck in there somewhere? That's happened to me before and that ended up being the culprit.

 

Pull the caliper and rotate. You may have a bad unit bearing (hub bearing). Also, you might need to add brake pad grease to the backs of the pads. Finally, ensure all the clips are installed on every pad ear. Last time pads were replaced, were new clips used? These also benefit from brake pad grease.

 

Yeah... what he said.. ^^^... that will eliminate the caliper and rotor and brake pads.

I'm with him, wheel bearing assembly.

 

I went back to diagnosing the squeal and used a stethoscope this time. I isolated the squeal to a dry axle seal, just behind the plastic oil slinger. I pulled the slinger out as far as I could, scrubbed the area behind it with a small toothbrush dipped in Simple Green, rinsed it well and dried it with compressed air. Then I gave the seal a shot of WD40 while rotating the wheel back and forth by hand. Apparently the axle seal was dry and squealed while rubbing against the axle shaft. I completed the procedure by spraying the axle/seal area with white lithium grease and pushed the oil slinger back into it's original position. No more high pitched squeal.

 

I have this same issue right now. Any chance you took pictures or video of the problem. Thanks!

 

Sorry, no pictures or videos.
For noise coming from the right front wheel area, just look into the wheel area from the front of the Jeep and you'll see the end of the axle shaft (on the left), the black plastic oil slinger, then the universal joint (on the right). The seal is to the left of the oil slinger that rides on the shaft and you can't see the seal behind it unless you slide the oil slinger to the right about 1/2 inch. Give that area a good cleaning and a shot of white lithium grease. There was also a slight squeal coming from the rear of the differential, I believe it's called the pinion seal, which you can't see but is behind the drive shaft that goes from the front differential to the transfer case. I also gave that tight area a shot of white lithium grease (stuff in a spray can) and it immediately quieted the slight squeal that was coming from that seal. I live in a hot humid climate and it seams that rubber or compound seals dry up quicker.