excentric

i have a defender 2004, ihave noticed a small patch looks like oil coming from round nearside swivel joint also their seems to be runs on the inside edge of the tyre ,it seems to stop by itself after a small discharge, if anybody can give me any advice please and is it safe to use.

I have a problem with back door central locking, back doors will not fully lock using the key fob, they go half way down but the doors remain open,which sets the alarm off. pushed down fully manually they work , any help would be useful, thankyou.