I just changed my oil using the MitiVac Fluid Evacuator Plus, 8.8 liter model. This unit made changing the oil so much easier than with the metal Topsider unit I used previously. The Topsider never sealed properly due to the flimsy tin cap for the pump. I would have to pump the Topsider many extra times throughout the oil change process just to get it to work. The MitiVac unit is a much superior design in my opinion. I ordered mine from The Tool Warehouse based on prior info posted here. The price of $56.05 is the best I've found. (I have no ties to MitiVac or The Tool Warehouse but am one happy camper now that I can convert my Topsider to a rather expensive gas can.)

MitiVac link