I don't have any experience or knowledge of the Tracloc but Summit has this rebuild kit:
http://www.summitracing.com/parts/yga-16027/overview/
.........or install this in and hope you get lucky with the set up.
http://www.summitracing.com/parts/dtl-913a586
I have a very good rear old differential guy here local and I've heard too many bad set ups by so called 'professionals' so I didn't hesitate to take my 12 bolt out and deliver it when I changed ring and pinion ratios.........guess what, it's silent and the lash is beautiful.