Mark make a Post on this question so everyone will see it and offer advice. It's probably brake squawl because the UDT is dirty or the wrong hydraulic fluid installed. Post it an see what everybody else thinks too.
Mark if your going to tear down the axle please get a Works Shop Manual. You will run into many more question doing this and even with the manual you will have questions. I can get you a discount on one through Carver Equipment just by mentioning OB1 to Tim Honeycutt....
Carver Equipment
1600 S. Clinton Ave.
Hwy 301 South
Dunn, NC 28334
910-892-7171
910-891-7171 (fax)