mma.se/47541

, Boxed -> False,
 Axes -> True,
 AxesEdge -> {{0, -1}, {1, 0}, {1, 0}},
 FaceGrids -> {
   {{-1, 0, 0}, {{},
     Range[0, Round[Max[Flatten[dxy, 1][[All, 3]]], 10], 20]}},
   {{0, -1, 0}, {{},
     Range[0, Round[Max[Flatten[dxy, 1][[All, 3]]], 10], 20]}}},
 FaceGridsStyle -> Directive[{Opacity@.5, Black, Thick}],
 ViewPoint -> {Pi, Pi/2, 2}]