OK, here's the deal guys... A couple of weeks ago I discovered that I had some chipped spider gears in my stock diff. while I was getting ready to install cobra rear brakes. I decided to go ahead and upgrade to the FRPP 31 spline diff., Alloy USA axles and all new bearings.
I had a friend help me with the install, he is an experienced mechanic and the install went flawlessly.
I noticed a sound coming from the rear end that I initially associated with the rear brake pads slightly engaged on the rotors. At the time I didn't realize that I needed to change the pads as well so I parked the car and put new rear pads on it, I also realized that the rotor had been making light contact with the new bracket so I got washers and spaced it out correctly ruling out the possibility of it being the rear brakes. Drove the car again and the sound still remained..
At this point I felt that it had to be something internal so we pulled the axles and the new axle bearings felt a little strange so I went ahead and changed them again, this time with Ford parts. Sound is still there...
We checked everything in the diff., there is no abnormal wear, play or anything out of the ordinary.
The only thing that I can think is that it might have something to do with the new axles & bearings breaking in (wearing the powder coat off) or possibly some kind of a problem with the manufacturing of the axles (unlikely since it is coming from both sides)?
The noise is a constant hum, like brake pads making very slight contact with a rotor and it comes from both sides of the rear end equally all the way out by the axle bearings. The noise DOES NOT change with speed, accel or decel so the gears are out. Axle tubes are welded and straight.
Sorry for the long drawn out story, but this is about to drive me completely insane. Any help would be really appreciated.
Important notes: The car only had about 10 miles driven on the first set of axle bearings. The noise was there immediately after installing the new second set of bearings.
I had a friend help me with the install, he is an experienced mechanic and the install went flawlessly.
I noticed a sound coming from the rear end that I initially associated with the rear brake pads slightly engaged on the rotors. At the time I didn't realize that I needed to change the pads as well so I parked the car and put new rear pads on it, I also realized that the rotor had been making light contact with the new bracket so I got washers and spaced it out correctly ruling out the possibility of it being the rear brakes. Drove the car again and the sound still remained..
At this point I felt that it had to be something internal so we pulled the axles and the new axle bearings felt a little strange so I went ahead and changed them again, this time with Ford parts. Sound is still there...
We checked everything in the diff., there is no abnormal wear, play or anything out of the ordinary.
The only thing that I can think is that it might have something to do with the new axles & bearings breaking in (wearing the powder coat off) or possibly some kind of a problem with the manufacturing of the axles (unlikely since it is coming from both sides)?
The noise is a constant hum, like brake pads making very slight contact with a rotor and it comes from both sides of the rear end equally all the way out by the axle bearings. The noise DOES NOT change with speed, accel or decel so the gears are out. Axle tubes are welded and straight.
Sorry for the long drawn out story, but this is about to drive me completely insane. Any help would be really appreciated.
Important notes: The car only had about 10 miles driven on the first set of axle bearings. The noise was there immediately after installing the new second set of bearings.
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