TLR 22 dif probs

[highlander]

had a test run in the week with my 22 ... all is good apart from after running not even five mins the diff has gone from super smooth to feeling like a bag af spanners ( rough to feel but still loose and working fine ) just dont feel great anyone else found this... tried a re grease but it feels just the same (looks like ceramic balls and new plates needed) dohh