man who dont hate the smell of diff oil or heavy gear oil?I hate the smell,takes a week to wash it of your skin?anyway for years Ive used one of those suck up tubes you fill then pump into a gearbox or diff,a few times over with mess,,well Im over it and decided to improvise,Ive seen these pump jiggers online same or similar more or less,i just took a cheapo garden spray pack thing,enlarged the outlet to take 10mm plastic hose (had 4mm)and all good,so easy,once oil comes out the fill hole,bend and squish the hose over,pull the air release valve to dump the pressure and done,still gonna be a drip or two but much easier,still gonna stink but less drips.