Rear End Noise

I have a rear end noise at 45 MPH on my 2000 LS V-8. This happened shortly after the brake pads and rotors were replaced with new OEM parts at 53,000 miles. I am aware of the half shaft TSB but this doesn't follow the symptoms stated in that TSB (moaning, droaning at 55 MPH in 5th gear). It occurs at 45 MPH and is about 1000 Hertz in frequency. It doesn't matter what gear you are in as long as you are doing 45 MPH. The more gas I give it at that speed, the louder it gets. I also had to replace the Right rear caliper bracket since it had a frozen guide pin. I assumed that maybe the bearing got damaged and replaced the Knuckle and Hub assy. The problem still remains. Has anybody had a problem like that and know what the cause was?

I have a rear end noise at 45 MPH on my 2000 LS V-8. This happened shortly after the brake pads and rotors were replaced with new OEM parts at 53,000 miles. I am aware of the half shaft TSB but this doesn't follow the symptoms stated in that TSB (moaning, droaning at 55 MPH in 5th gear). It occurs at 45 MPH and is about 1000 Hertz in frequency. It doesn't matter what gear you are in as long as you are doing 45 MPH. The more gas I give it at that speed, the louder it gets. I also had to replace the Right rear caliper bracket since it had a frozen guide pin. I assumed that maybe the bearing got damaged and replaced the Knuckle and Hub assy. The problem still remains. Has anybody had a problem like that and know what the cause was?
could be a hub bearing, or differential bearings

Well I finally got the rear noise problem fixed. I tried to get Lincoln to pay for it but I had to have the dealer diagnose it first. So, I took it to the place where I bought it: Palm Springs Motors, a place you don't want to go to. The diagnoses was to cost $80.00 and I would have the car back before the end of the day. The dealer was given all the correspondence from Lincoln Customer Service. I got a call at 10:45 AM telling me that it has to go to Heavy Line and it would be 3-4 days minimum before they could look at it. I would have to leave the car and of course pay for my rental all that time. This was not acceptable. I also let Lincoln know about my experience and that this was my last Ford product. Their reply was that they can't force a dealer to do anything since it is a franchise but they told me I could tell the dealer about my experience (like they would do anything). So, I took it to an Independent Shop that specializes in Ford. They found that the Pinion Bearings were the problem. There were also chips in the Spider gears. Both those items were replaced as were all the rest of the bearings and seals as a matter of convenience and necessity. The only things not replaced were the Pinion and Ring gears and of course the case. The Mechanic stated that they had new Torque specs. for the differential and mine were too tight which led to the premature failure. The noise is now gone and I hope for another 50,000 miles minimum. I don't know if I can post pictures here but I have the old parts to photograph if I can at a later date.