I think add black grease or not would be personal preferences and also depending on how to maintain the car.
Added some lubrications does "feel smoother", however, it is to avoid the black grease get into the diff... I think....
大家交流下:其實行一陣,D grease會去左邊呢! 去左底部。。什麼drag break, 我feel 吳到。不過Ben Gor 和ftbingobingo Gor 的end result 不一樣是:一個有多餘grease,一個是沒有grease多。不過一樣會smooth with protection.
我沒有很多玩車experience, 也只在MX行過下。 difference point of view is good in a way to share ideas, but not to pin point others. 睇這個post 學多左set 車technique 是真的。多謝各位C Hing!