friend of mine has old soda surup jugs from years ago. like the ones you used at the stores / dinners / were ever bulk soda was needed. he got some hose ends with the quick couplers also that go on them.
then used a 3ft hose for output on each one. and a air hose fitting on each one for air inlet.
then he filled each one with what he wanted like gear oil / coolent / atf / what ever else he wants. then when he needs some air it up 20-30 psi . crack the small valve on the output hose and just fill and turn off when done.
man does this setup work on the trail good to. and cold winter time gear oil fill ups are a snap now with 20-30 psi behind the cold stuff.