Lubricant Storage
It is recommended that drums NOT be stored directly on concrete, as this can set up a slight electrical charge and some additives can precipitate to the bottom -much like storing a battery on a concrete floor – and this might have a sludge like appearance.I recommend that drums be stored off the ground (at least use 2 x 4s), on their side.
IF drums are stored on end with the bung exposed it could draw in condensation which would gravitate to the bottom and look like “sludge”.