I would check out the vacuum lines ^^ as stated above, but also drain the torque converter and transmission pan. The filter/gasket kit shouldn't be more than about $30 from Fastlane and includes the gasket, filter, and any other seals necessary. When I did my 94 e320 trans fluid/filter (trans 722.369) it took about 6.5 - 7 quarts (I used Mobile 1 synthetic)