What 9-1/4" do you have? The recent 2005-ish area corporate LSD's have had some issues.
I've heard of narrowing issues due to the tube style that changes diameter.
My dads 2004 ram has a 9 1/4 rear and at 125000 miles the rear locked up. Turs out the axle seals leaked gear oil and locked it up, it was a fairly easy rebuild though.