it depends where you measure it from. if you are just holding on to the tailshaft and checking it there then you will get a little bit more that you expect as it is getting the play from all of the gears in the diff and not just the crownwheel and pinion. to measure it properly you need to set up a dial gauge on the crownwheel and hold the pinion still and check the play there .13 of a mm is about norm. racers have a bit more to allow for heat expansion etc etc but in a road car .13 is good