Originally Posted by mikeygar

could be your o-rings are swollen, pressing hard the washer under the pin. I had that same problem and my diffs felt really tight and gritty. My 3k diff felt heavier than a 5k diff from an older car. Upon inspection the metal washer had wide scratch marks which probably caused the rough and heavy feel.

I changed my o-rings from the orange ones to the black ones (BD-500GM) and diffs now feel free with no binding.